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Map Suite
Desktop .NET GIS Component

Common Questions and Answers About Map Suite Desktop

Click on any of the frequently asked questions below to be taken to the answer.

If I have the latitude and longitude of a point, how can I plot it on a map?

All you need to do is, 1) Create a new point, 2) Add that point to the map.

Create a new Winforms project, add a map (name it Map1) to the form, and add the following code to the form's load event:

C#

// This first section is simply to get get a map of the US to show

map1.MapUnit = MapSuite.Geometry.MapLengthUnits.DecimalDegrees;

MapSuite.Layer lyr = new MapSuite.Layer(@"..\..\sampledata\world\cntry02.shp");

lyr.ZoomLevelExtentUnit = MapSuite.Geometry.ZoomLevelExtentUnits.miles;

MapSuite.ZoomLevel t = new MapSuite.ZoomLevel(30000, 0);

MapSuite.AreaSymbol area = new MapSuite.AreaSymbol(new GeoPen(GeoColor.KnownColors.Black, 1), new GeoSolidBrush(GeoColor.KnownColors.LightGray));

MapSuite.SymbolRenderer sr = new MapSuite.SymbolRenderer(area);

t.GeoStyle.SymbolRenderers.Add(sr);

lyr.CustomZoomLevels.Add(t);

map1.Layers.Add(lyr);

 

// This second section is all you need to plot a point if you have the latitude and longitude

MapSuite.Geometry.PointShape ps = new MapSuite.Geometry.PointShape(-119.09, 34.32);

map1.MapShapes.Add(new MapSuite.PointMapShape(ps, new MapSuite.PointSymbol(MapSuite.PointStyleEnum.Circle)));

 

//This third section shows how to add a label for the point

MapSuite.TextSymbol ts = new MapSuite.TextSymbol(new GeoFont("Arial", 8), new GeoSolidBrush(GeoColor.KnownColors.Blue), 0, 10);

map1.MapShapes[0].TextSymbols.Add(ts);

map1.MapShapes[0].Name = "Los Angeles";

map1.Refresh(); 

VB.NET

' This first section is simply to get get a map of the US to show

map1.MapUnit = MapSuite.Geometry.MapLengthUnits.DecimalDegrees

Dim lyr As New MapSuite.Layer("..\..\sampledata\world\cntry02.shp")

lyr.ZoomLevelExtentUnit = MapSuite.Geometry. ZoomLevelExtentUnits.miles

Dim t As New MapSuite.ZoomLevel(30000, 0)

Dim area As New MapSuite.AreaSymbol(New GeoPen(GeoColor.KnownColors.Black, 1), New GeoSolidBrush(GeoColor.KnownColors.LightGray))

Dim sr As New MapSuite.SymbolRenderer(area)

t.GeoStyle.SymbolRenderers.Add(sr)

lyr.CustomZoomLevels.Add(t)

map1.Layers.Add(lyr)

 

' This second section is all you need to plot a point if you have the latitude and longitude

Dim ps As New MapSuite.Geometry.PointShape(-119.09, 34.32)

map1.MapShapes.Add(New MapSuite.PointMapShape(ps, New MapSuite.PointSymbol(MapSuite.PointStyleEnum.Circle)))

 

'This third section shows how to add a label for the point

Dim ts As New MapSuite.TextSymbol(New GeoFont("Arial", 8), New GeoSolidBrush(GeoColor.KnownColors.Blue), 0, 10)

map1.MapShapes(0).TextSymbols.Add(ts)

map1.MapShapes(0).Name = "Los Angeles"

map1.Refresh() 

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I would like to have more custom properties (like a tag property) on a map shape object. How can I add my own properties?

Adding custom properties is quite easy. All you have to do is inherit from one of the classes and add your own custom properties, like in the following code:

C#

public class MyPointMapShape : PointMapShape

{

public MyPointMapShape(PointShape PointShape, PointSymbol PointSymbol)

: base(PointShape, PointSymbol)

{

}

 

string _Tag = string.Empty;

 

public string Tag

{

get

{

return _Tag;

}

set

{

_Tag = value;

}

}

} 

 

VB.NET

Public Class MyPointMapShape

Inherits PointMapShape

Public Sub New(ByVal PointShape As PointShape, ByVal PointSymbol As PointSymbol)

MyBase.New(PointShape, PointSymbol)

End Sub

 

Private _Tag As String = String.Empty

 

Public Property Tag() As String

Get

Return _Tag

End Get

Set(ByVal value As String)

_Tag = value

End Set

End Property

End Class 

From here, you can add as many custom properties as you would like.

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How do I convert screen coordinates into world coordinates?

The map control has a method ToWorldCoordinate which takes in a PointF object (a point in canvas / screen coordinates). Returned is a PointR object (a point in world coordinates).

C#

System.Drawing.PointF controlPointF = new System.Drawing.PointF(45, 34);

PointR pointR = Map1.ToWorldCoordinate(controlPointF);

PointShape p0 = new PointShape(pointR.X, pointR.Y);

VB.NET

Dim controlPointF As New System.Drawing.PointF(45, 34)

Dim pointR As PointR = Map1.ToWorldCoordinate(controlPointF)

Dim p0 As New PointShape(pointR.X, pointR.Y)

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How do I convert world coordinates into screen coordinates?

The map control has a method ToCanvasCoordinate which takes in a PointR object (a point in world coordinates). Returned is a PointF object (a point in canvas / screen coordinates).

C#

PointShape pointShape = new PointShape(-119.09, 34.32);

System.Drawing.PointF screetPoint = Map1.ToCanvasCoordinate(pointShape.X, pointShape.Y);

VB.NET

Dim pointShape As New PointShape(-119.09, 34.32)

Dim screetPoint As System.Drawing.PointF = Map1.ToCanvasCoordinate(pointShape.X, pointShape.Y)

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How can I find a map shape when the user clicks it?

First, set the Map.Mode to ModeType.SelectMapShapes. Once this is done, every time a map shape is clicked, the Map.SelectMapShapes event will fire, passing in the map shapes that were selected. It is the map shapes (plural) because you could have more than one map shape in one location. Therefore, when that location is clicked, it is unclear which map shape was meant. So, it is actually an array of map shapes. Here is the code to make it clearer. Note: The Geometry sample named "Select Map Shapes Mode" can show you more detail on this.

VB.NET

private void Map1_SelectMapShapes(MapSuite.BaseMapShape[] MapShapes)

{

if (MapShapes != null)

MessageBox.Show(MapShapes[0].Name);

} 

 

VB.NET

Private Sub Map1_SelectMapShapes(ByVal MapShapes As MapSuite.BaseMapShape())

If MapShapes IsNot Nothing Then

MessageBox.Show(MapShapes(0).Name)

End If

End Sub 

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How can I find a feature (road, city, etc.) when the user clicks it?

First, set the Map.Mode to ModeType.SelectFeatures. Once this is done, every time a feature is clicked, the Map.SelectFeatures event will fire, passing in the features that were selected. It is the features (plural) because you could have more than one feature in one location (for example, a bridge crossing over a river). Here is the code to make it clearer. Note: The Query sample named "Select Features Mode" can show you more detail on this.

C#

private void Map1_SelectFeatures(MapSuite.FeatureInfo[] FeatureInfos)

{

if (FeatureInfos != null)

MessageBox.Show(FeatureInfos[0].RecordNumber.ToString());

} 

VB.NET

Private Sub Map1_SelectFeatures(ByVal FeatureInfos As MapSuite.FeatureInfo())

If FeatureInfos IsNot Nothing Then

MessageBox.Show(FeatureInfos(0).RecordNumber.ToString())

End If

End Sub 

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How can I zoom in on an area based on a query?

First, you need to create a custom field object, but the real work comes from calling GetRecordsExtents function from the layer object to see the extent you need to use. Below is some code to make this a little clearer.

C#

//Here you would set the record numbers to something meaningful in your your system

int[] RecordNumbers = new int[2];

RecordNumbers[0] = 2;

RecordNumbers[1] = 5;

RecordNumbers[2] = 17;

 

//Setup new extent that will show all three of the selected records

RectangleR NewExtent = Map1.Layers[0].GetRecordsExtents(RecordNumbers);

 

//Scale the extent up just a little (10%) to make it more viewable

NewExtent.ScaleUp(10);

 

//Set the map's current extent to the extent we just created

Map1.CurrentExtent = NewExtent; 

VB.NET

'Here you would set the record numbers to something meaningful in your your system

Dim RecordNumbers As Integer() = New Integer(1) {}

RecordNumbers(0) = 2

RecordNumbers(1) = 5

RecordNumbers(2) = 17

 

'Setup new extent that will show all three of the selected records

Dim NewExtent As RectangleR = Map1.Layers(0).GetRecordsExtents(RecordNumbers)

 

'Scale the extent up just a little (10%) to make it more viewable

NewExtent.ScaleUp(10)

 

'Set the map's current extent to the extent we just created

Map1.CurrentExtent = NewExtent 

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I see a layer can have different zoomlevels. What would I use this feature for?

Imagine you have an application which maps a traveler's journey between two points. You would, likely, start by showing the entire US as the full extent. At this level, you would show the states and maybe the interstate and US highways. As the user zooms in to a single state, you might show state highways. As they zoom in more you might show county roads. As they zoom in so they are looking at a city, you could show all the city streets.

In such an application you would need to setup different zoomlevels to control what is shown to the user and when (otherwise, the map would be too cluttered). In this example, you would setup a zoomlevel to show states, interstate and US highways. This zoomlevel would be setup to show when the user was at any zoom level (say between 30,000 miles across and 0 miles across). Then another zoomlevel would be created to show state highways when the user is zoomed into the state level (say between 750 miles across and 0 miles across). You keep setting up more and more zoomlevels like this. Your final zoomlevel would be to show the city streets when the user is zoomed to between 10 miles across and 0 miles across). You may notice that all of the zoomlevels here are set to keep showing as the user zooms in (the second parameter is 0 miles across). You could also set one or more zoomlevels to stop showing once zoomed in too close to something.

The Misc sample named "ZoomLevels" can show you in more detail how to use zoomlevels.

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How can I get information about point or feature from a dbf file?

Using Layer.DataQuery you can get all the information available in the dbf file. This routine takes in either a SQL string or record number(s). If you have the record number of the point you want information about (23 in this example), you would use the following code to get the data about that point from the dbf file into a DataTable object:

C#

DataTable dt = Map1.Layers[0].DataQuery(23, false);

VB.NET

Dim dt as DataTable = Map1.Layers.Item(0).DataQuery(23, False) 

The Querying sample "Combination Query" will show you more detail on this topic.

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Once I have a record number, how can I get the shape for that record?

Using Layer.GetShape you can get the shape object for a record (in “Shapes From Layer” sample). The following code would accomplish this:

C#

MapSuite.Geometry.BaseShape shape = Map1.Layers[0].GetShape(23);

VB.NET

Dim shape as MapSuite.Geometry.BaseShape = Map1.Layers.Item(0).GetShape(23)

You could also use Layer.DataQuery with the following code (this will return all the dbf file information as well as the shape):

C#

DataTable dt = Map1.Layers[0].DataQuery(23, true);

VB.NET

Dim dt as DataTable = Map1.Layers.Item(0).DataQuery(23, True)

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How can I zoom in or out programmatically?

Zooming in or out is quite easy – you can do it with a single line of code:

C#

Map1.ZoomIn(40); // This will zoom in 40%

 

Map1.ZoomOut(40); // This will zoom out 40% 

VB.NET

map1.ZoomIn(40) '-- This will zoom in 40%

 

map1.ZoomOut(40) '-- This will zoom out 40% 

You can see this code in every sample under the routine ToolBar1_ButtonClick which is used by the menu and the toolbar.

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How can I set the full extent of a map to something specific?

The Map1.FullExtent is a read-only property so you cannot change it but you can easily accomplish your task by creating your own extent and when the user clicks on your "Full Extent" menu item/toolbar button you just assign your custom extent to the map's current extent. The following code shows you how.

C#

// First you need a module level variable to hold the custom full extent
RectangleR rect;

// Then (in some routine) set the map so that it is showing the extent that
// will be your custom full extent, saving that in the variable
rect = Map1.CurrentExtent;

// Then, when you want to go to your custom full extent, just assign the variable to the map's current extent
Map1.CurrentExtent = rect;

VB.NET

' First you need a module level variable to hold the custom full extent

Dim rect As RectangleR

 

' Then (in some routine) set the map so that it is showing the extent that

' will be your custom full extent, saving that in the variable

rect = Map1.CurrentExtent

 

' Then, when you want to go to your custom full extent, just assign the variable to the map's current extent

Map1.CurrentExtent = rect 

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How can I display my data so each item falls within some group? For example, if I have several cities with different populations, how could I group these cities into the categories of small, medium, and large, each with its own symbol on the map?

To accomplish this you would use class breaks. You can see the Rendering sample named "Label Value Renderer" (or another one is Class Break Renderer) for more detail. Basically, you need to create a series of class breaks and one class break cap to group the data. For example, let's use the example of cities, like in Label Value Renderer. In that sample, each listed city falls into one of five categories: Less than 500,000; 500,000 - 999,999; 1,000,000 - 1,999,999; 2,000,000 - 4,999,999; and 5,000,000 and over. When we setup the class breaks, you'll see how it works. The code below accomplishes the task.

C#

// First we need to setup the zoomLevel and collection
ZoomLevel customZoomLevel = new ZoomLevel(10000, 2500);

SymbolClassBreakCollection classbreaks = new SymbolClassBreakCollection();

 

// Create first break, which is 'Under 500,000' and add it to the collection

SymbolClassBreakRenderer.ClassBreak breaks;

breaks = new SymbolClassBreakRenderer.ClassBreak(500000, mSymbol1);

classbreaks.Add(breaks);

 

// Create second break, which is 'Under 1,000,000' and add it to the collection

breaks = new SymbolClassBreakRenderer.ClassBreak(1000000, mSymbol2);

classbreaks.Add(breaks);

 

// Create third break, which is 'Under 2,000,000' and add it to the collection

breaks = new SymbolClassBreakRenderer.ClassBreak(2000000, mSymbol3);

classbreaks.Add(breaks);

 

// Create cap, which will handle the final two categories. Every class break collection must end with a cap

// In this case, the cap says, everything over 5,000,000 should get Symbol5 and under 5,000,000 will get Symbol4

SymbolClassBreakRenderer.ClassBreakCap cap;

cap = new SymbolClassBreakRenderer.ClassBreakCap(5000000, mSymbol5, mSymbol4);

classbreaks.Add(cap);

 

// Now, we just add the class break collection to a renderer and add the renderer to the zoomLevel

SymbolClassBreakRenderer rend = new SymbolClassBreakRenderer("population", classbreaks);

customZoomLevel.GeoStyle.SymbolRenderers.Add(rend);

// At this point, we have setup our class breaks.

VB.NET

' First we need to setup the zoomLevel and collection

Dim customZoomLevel As New ZoomLevel(10000, 2500)

Dim classbreaks As New SymbolClassBreakCollection()

 

' Create first break, which is 'Under 500,000' and add it to the collection

Dim breaks As SymbolClassBreakRenderer.ClassBreak

breaks = New SymbolClassBreakRenderer.ClassBreak(500000, mSymbol1)

classbreaks.Add(breaks)

 

' Create second break, which is 'Under 1,000,000' and add it to the collection

breaks = New SymbolClassBreakRenderer.ClassBreak(1000000, mSymbol2)

classbreaks.Add(breaks)

 

' Create third break, which is 'Under 2,000,000' and add it to the collection

breaks = New SymbolClassBreakRenderer.ClassBreak(2000000, mSymbol3)

classbreaks.Add(breaks)

 

' Create cap, which will handle the final two categories. Every class break collection must end with a cap

' In this case, the cap says, everything over 5,000,000 should get Symbol5 and under 5,000,000 will get Symbol4

Dim cap As SymbolClassBreakRenderer.ClassBreakCap

cap = New SymbolClassBreakRenderer.ClassBreakCap(5000000, mSymbol5, mSymbol4)

classbreaks.Add(cap)

 

' Now, we just add the class break collection to a renderer and add the renderer to the zoomLevel

Dim rend As New SymbolClassBreakRenderer("population", classbreaks)

customZoomLevel.GeoStyle.SymbolRenderers.Add(rend)

 

' At this point, we have setup our class breaks. 

When you are this far, you have the class breaks setup. It is important that you remember that the sequence is quite important. The sequence in which the class breaks are added to the collection will determine into which class each value falls. The logic will work something like the following.

  • For each value to be put into a class break (for each city in this example)
  • Compare to each class break
  • Does the current value fall below the current class break level?
  • If yes, then the current value is assigned to the current class break, go to the next value (city).
  • If no, then go to the next class break.
  • If we get to the class break cap and the current value is higher than the cap (5,000,000 in this example) then assign to the highest class break, regardless of how high the value is.

So, if you add the class breaks in a different order, expect different results.

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How can I display my data so each item is represented with a special symbol based on an exact textual match (not categories, classes or ranges)? For example, a lake should be blue; a dry lake should be brown, etc.

To accomplish this you would use symbol value renderers. You can see the Rendering sample named "Value Renderer" for more detail. You need to create a collection to hold the values to match and then setup a symbol for each value ('Lake', 'Dry Lake', etc.). See the following code.

C#

// First we need to setup the zoomLevel and collection
ZoomLevel customZoomLevel = new ZoomLevel(10000, 0);

SymbolValueCollection values = new SymbolValueCollection();

SymbolValueRenderer.Value val;

AreaSymbol sym;

 

// Add renderer value for any record named "Lake". This will be a simple light sky blue color for a lake

sym = new AreaSymbol(new GeoPen(GeoColor.FromArgb(0, 0, 0, 0)), new GeoSolidBrush(GeoColor.KnownColors.LightSkyBlue));

val = new SymbolValueRenderer.Value("Lake", sym);

values.Add(val);

 

// Add renderer value for any record named "Dry Lake". This will be an actual graphic that looks like a dry lake

Bitmap bmp = new Bitmap(@"..\..\SampleData\Textures\rust pebbles.bmp");

sym = new AreaSymbol(new GeoPen(GeoColor.FromArgb(0, 0, 0, 0)), new GeoTextureBrush(bmp));

val = new SymbolValueRenderer.Value("Lake Dry", sym);

values.Add(val);

 

// Now, we must create the renderer (collection of values) and add it to the zoomLevel

SymbolValueRenderer rend = new SymbolValueRenderer("Feature", values);

customZoomLevel.GeoStyle.SymbolRenderers.Add(rend);

// At this point, lakes and dry lakes are configured to show using the symbols we specified
// all you need to do now is add the zoomLevel to the layer and add the layer to the map

VB.NET

' First we need to setup the zoomLevel and collection

Dim customZoomLevel As New ZoomLevel(10000, 0)

Dim values As New SymbolValueCollection()

Dim val As SymbolValueRenderer.Value

Dim sym As AreaSymbol

 

' Add renderer value for any record named "Lake". This will be a simple light sky blue color for a lake

sym = New AreaSymbol(New GeoPen(GeoColor.FromArgb(0, 0, 0, 0)), New GeoSolidBrush(GeoColor.KnownColors.LightSkyBlue))

val = New SymbolValueRenderer.Value("Lake", sym)

values.Add(val)

 

' Add renderer value for any record named "Dry Lake". This will be an actual graphic that looks like a dry lake

Dim bmp As New Bitmap("..\..\SampleData\Textures\rust pebbles.bmp")

sym = New AreaSymbol(New GeoPen(GeoColor.FromArgb(0, 0, 0, 0)), New GeoTextureBrush(bmp))

val = New SymbolValueRenderer.Value("Lake Dry", sym)

values.Add(val)

 

' Now, we must create the renderer (collection of values) and add it to the zoomLevel

Dim rend As New SymbolValueRenderer("Feature", values)

customZoomLevel.GeoStyle.SymbolRenderers.Add(rend)

 

' At this point, lakes and dry lakes are configured to show using the symbols we specified

' all you need to do now is add the zoomLevel to the layer and add the layer to the map 

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How can I use my own rendering logic when the symbol representing a place's location is being drawn?

Setting up your own rendering logic for this is quite easy. You can see the Rendering sample named "Custom Symbols" for a more detailed example on how to accomplish this but simply put, all you need to do is create a module level variable of type PointSymbol and then wire-up a custom draw event to handle that object's drawing. The following code should make it clearer:

C#

// Module-level variable to represent the point symbol for each location
internal PointSymbol mCustomPointSymbol;

// Then, create the custom draw routine

private void mCustomPointSymbol_CustomDraw(System.Drawing.Graphics g, System.Drawing.PointF PointF, MapSuite.PointSymbol symbol)
{
// Logic for custom drawing of symbol used for each city – this will draw a star-burst with a yellow center
GraphicsPath path = new GraphicsPath();

Rectangle R = new Rectangle(Convert.ToInt32(PointF.X - 10), Convert.ToInt32(PointF.Y - 10), 20, 20);

path.AddEllipse(R);

PathGradientBrush brush = new PathGradientBrush(path.PathPoints);

Color[] c = { Color.FromArgb(0, 0, 0, 0) };

brush.CenterColor = Color.Yellow;

brush.SurroundColors = c;

brush.FocusScales = new PointF(Convert.ToSingle(0.01), Convert.ToSingle(0.01));

g.FillEllipse(brush, R);

brush.Dispose();
}

// Then, in the form's load event, instantiate the variable and wire-up the custom draw routine
private void CustomSymbolsApp_Load(object sender, System.EventArgs e)
{
mCustomPointSymbol = new PointSymbol(PointStyleEnum.Custom);

mCustomPointSymbol.CustomDraw += new PointSymbol.CustomDrawEventHandler(this.mCustomPointSymbol_CustomDraw);
}

VB.NET

'-- Module-level variable to represent the point symbol for each location
Friend mCustomPointSymbol As PointSymbol

' Module-level variable to represent the point symbol for each location

 

' Then, create the custom draw routine

Private Sub mCustomPointSymbol_CustomDraw(ByVal g As System.Drawing.Graphics, ByVal PointF As System.Drawing.PointF, ByVal symbol As MapSuite.PointSymbol)

' Logic for custom drawing of symbol used for each city – this will draw a star-burst with a yellow center

Dim path As New GraphicsPath()

Dim R As New Rectangle(Convert.ToInt32(PointF.X - 10), Convert.ToInt32(PointF.Y - 10), 20, 20)

path.AddEllipse(R)

Dim brush As New PathGradientBrush(path.PathPoints)

Dim c As Color() = {Color.FromArgb(0, 0, 0, 0)}

brush.CenterColor = Color.Yellow

brush.SurroundColors = c

brush.FocusScales = New PointF(Convert.ToSingle(0.01), Convert.ToSingle(0.01))

g.FillEllipse(brush, R)

brush.Dispose()

End Sub

 

' Then, in the form's load event, instantiate the variable and wire-up the custom draw routine

Private Sub CustomSymbolsApp_Load(ByVal sender As Object, ByVal e As System.EventArgs)

mCustomPointSymbol = New PointSymbol(PointStyleEnum.[Custom])

AddHandler mCustomPointSymbol.CustomDraw, AddressOf Me.mCustomPointSymbol_CustomDraw

End Sub

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How can I have items labeled differently based on a value in a field in the shape file? For example, if I have several cities in each country in Europe, I want to show capitals in a larger font than non-capitals.

To accomplish this you would use the label value renderer. You can see the Rendering sample named "Label Value Renderers" for more detail. You need to create a label value collection and add to that collection one label value for each value to be match. In this example, we will have two label values; one for "Y" and one for "N" in the field named "Capital." The code below does just that.

C#

// First we need to setup the zoomLevel and collection
ZoomLevel t2 = new ZoomLevel(2500, 0);

LabelValueCollection col = new LabelValueCollection();

LabelValueRenderer.LabelValue val;

TextSymbol sym;

 

// Setup for capitals

sym = new TextSymbol(new GeoFont("Arial", 12, GeoFontStyle.Bold), new GeoSolidBrush(GeoColor.KnownColors.Black), 0, -8);

val = new LabelValueRenderer.LabelValue("Y", sym);

col.Add(val);

 

// Setup for non-capitals

sym = new TextSymbol(new GeoFont("Arial", 8, GeoFontStyle.Bold), new GeoSolidBrush(GeoColor.KnownColors.Black), 0, -6);

val = new LabelValueRenderer.LabelValue("N", sym);

col.Add(val);

 

// Create renderer, testing field "Capital" but displaying field "Name"

LabelValueRenderer rend = new LabelValueRenderer("Capital", "Name", col);

 

// Add renderer to the zoomLevel

t2.GeoTextStyle.LabelRenderers.Add(rend);

VB.NET

Dim t2 As New ZoomLevel(2500, 0)

Dim col As New LabelValueCollection()

Dim val As LabelValueRenderer.LabelValue

Dim sym As TextSymbol

 

' Setup for capitals

sym = New TextSymbol(New GeoFont("Arial", 12, GeoFontStyle.Bold), New GeoSolidBrush(GeoColor.KnownColors.Black), 0, -8)

val = New LabelValueRenderer.LabelValue("Y", sym)

col.Add(val)

 

' Setup for non-capitals

sym = New TextSymbol(New GeoFont("Arial", 8, GeoFontStyle.Bold), New GeoSolidBrush(GeoColor.KnownColors.Black), 0, -6)

val = New LabelValueRenderer.LabelValue("N", sym)

col.Add(val)

 

' Create renderer, testing field "Capital" but displaying field "Name"

Dim rend As New LabelValueRenderer("Capital", "Name", col)

 

' Add renderer to the zoomLevel

t2.GeoTextStyle.LabelRenderers.Add(rend) 

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I see that a map can have multiple layers. Why would I use multiple layers?

Since a layer is the object that holds the data (that is a layer has one and only one shape file as its data source) if you want to have multiple data sources then you need multiple layers. The Misc sample named "ZoomLevels" can show you more details about this. In this sample, you will see five layers created. One layer has the streets of Austin, one layer has the countries, one layer has the details about the US states, etc. The zoomlevels in this sample just, in effect, tell each layer to render only at certain zoom factors. The point is that each layer actually has the data from the shape file. So, multiple shape files mean multiple layers.

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How can I print a map?

If you just want to print the map, it is quite easy. The Rendering sample named "Printing " shows how it is done, but the code is the following:

C#

PrintPreviewDialog print = new PrintPreviewDialog();

Map1.PrintDocument.DefaultPageSettings.Landscape = true;

print.Document = Map1.PrintDocument;

print.ShowDialog(); 

VB.NET

Dim print As New PrintPreviewDialog()

Map1.PrintDocument.DefaultPageSettings.Landscape = True

print.Document = Map1.PrintDocument

print.ShowDialog() 

At this point, the user will see the print preview dialog and can print just by pressing the print button.

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How can I print a map if I want to include my own logic? For example, if I want to include a legend or some additional text?

The Misc sample named "Printing" shows how it is done but the basics are this. You create a module level variable to hold the print document. You also wire up the PrintPage event so that when the map prints, you will get an event and you can add all the logic you want. The following code should make it clearer:

C#

// Module-level variable
private PrintDocument mPrintDocument = new PrintDocument();

// Logic when you want to show the print preview window
PrintPreviewDialog print = new PrintPreviewDialog();
mPrintDocument.DefaultPageSettings.Landscape = true;
print.Document = mPrintDocument;
print.ShowDialog();

// You'll also need to add this to the form's load event to wire up the custom print event
mPrintDocument.PrintPage += new PrintPageEventHandler(mPrintDocument_PrintPage);

// Finally, you will need to add the routine for the event

private void mPrintDocument_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
{
// Put your own custom drawing logic here

// Here we will use a simplified version of the code in the printing sample
// First, draw the map with a border
 Bitmap b = map1.GetBitmap(820, 580, false);

e.Graphics.DrawImage(b, 200, 120);

e.Graphics.DrawRectangle(new Pen(Color.Black, 2), new Rectangle(200, 120, Misc.GetBitmapScreenWidth(b), Misc.GetBitmapScreenHeight(b)));

 

// Next draw a title on the page

e.Graphics.DrawString("This is the title for the page", new Font("Arial", 15, FontStyle.Bold), new SolidBrush(Color.Black), 310, 54);
// Add as much logic as you would like
}

VB.NET

'-- Module-level variable
Private mPrintDocument As New PrintDocument()

'-- Logic when you want to show the print preview window
Dim print As New PrintPreviewDialog()

mPrintDocument.DefaultPageSettings.Landscape = True

print.Document = mPrintDocument

print.ShowDialog()

 

'-- You'll also need to add this to the form's load event to wire up the custom print event

AddHandler mPrintDocument.PrintPage, AddressOf mPrintDocument_PrintPage

'-- Finally, you will need to add the routine for the event
Private Sub mPrintDocument_PrintPage(ByVal sender As Object, ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles mPrintDocument.PrintPage

' Put your own custom drawing logic here

 

' Here we will use a simplified version of the code in the printing sample

' First, draw the map with a border

Dim b As Bitmap = map1.GetBitmap(820, 580, False)

e.Graphics.DrawImage(b, 200, 120)

e.Graphics.DrawRectangle(New Pen(Color.Black, 2), New Rectangle(200, 120, Misc.GetBitmapScreenWidth(b), Misc.GetBitmapScreenHeight(b)))

 

' Next draw a title on the page

e.Graphics.DrawString("This is the title for the page", New Font("Arial", 15, FontStyle.Bold), New SolidBrush(Color.Black), 310, 54)

' Add as much logic as you would like

End Sub

 

At this point, the user will see the print preview dialog and can print just by pressing the print button. All of your custom logic will be shown in the print preview dialog.

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I want a user to be able to draw various shapes (circles, rectangles, etc.) and I want to execute some custom logic while the shape is being created. How can I do this?

The Misc sample named "Track Shapes" will be very helpful to you in understanding how to accomplish this. In this sample there are no layers, no shape files, just track shapes being drawn (they can also be moved). As you can see from the code in this sample, there are plenty of events which you can tie into. You can execute your logic when the shape is just starting to be dragged, when the dragging is complete, or while the dragging is happening. As well, you can run your logic while the track shape is being drawn or when the drawing is complete. All of these events are used in the sample.

While the track shape is being drawn, you will see that there is logic to show the total area / perimeter / radius of the shape. When the track shape is finished being drawn, you will see logic to make the shape permanent (actually add it to the map as a map shape).

Explore this sample and it should be pretty clear how to accomplish these things. Below is a bit of the logic from the sample which is in the Map1_TrackShapesDraw event.

C#

private void map1_TrackShapesDraw(int X, int Y, System.Drawing.Graphics G)
{
// This code shows how to add the total area and perimeter to a track rectangle as it is being drawn
double Area, Perimeter;

string AreaUnit = "squarekm";

string LengthUnit = "kilometres";

Area = Map1.TrackRectangle.get_Area(MapAreaUnits.squarekm);

Perimeter = Map1.TrackRectangle.get_Perimeter(MapLengthUnits.kilometres);

G.DrawString("Area: " + Math.Round(Area, 2) + AreaUnit, new Font("Arial", 9, FontStyle.Bold), new SolidBrush(Color.Black), X, Y - 30);

G.DrawString("Perimeter: " + Math.Round(Perimeter, 2) + LengthUnit, new Font("Arial", 9, FontStyle.Bold), new SolidBrush(Color.Black), X, Y - 16);
}

VB.NET

Private Sub map1_TrackShapesDraw(ByVal X As Integer, ByVal Y As Integer, ByVal G As System.Drawing.Graphics)

' This code shows how to add the total area and perimeter to a track rectangle as it is being drawn

Dim Area As Double, Perimeter As Double

Dim AreaUnit As String = "squarekm"

Dim LengthUnit As String = "kilometres"

Area = Map1.TrackRectangle.get_Area(MapAreaUnits.squarekm)

Perimeter = Map1.TrackRectangle.get_Perimeter(MapLengthUnits.kilometres)

G.DrawString("Area: " + Math.Round(Area, 2) + AreaUnit, New Font("Arial", 9, FontStyle.Bold), New SolidBrush(Color.Black), X, Y - 30)

G.DrawString("Perimeter: " + Math.Round(Perimeter, 2) + LengthUnit, New Font("Arial", 9, FontStyle.Bold), New SolidBrush(Color.Black), X, Y - 16)

End Sub 

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What are map shapes and how can I use them?

The Misc sample named "Track Shapes" will show you how to create map shapes based on a track shape (a shape a user draws). A map shape is a shape that is added via code and not from a shape file. That is, mostly shapes will be added from shape files (roads, buildings, etc.) but you might want to have your own shapes. Your own shapes might include proposed buildings or even vehicles driving down the street.

Map shapes can be easily moved and reside outside the context of layers. Map shapes are on the map, not on a layer. Let's say you want to allow a user to plot the points, on a map of the world, where they have visited. For this, you would load a layer with data of the world. Then you would set the map into track point mode. Then, let the user click creating the various points. Each time the user clicks, the Map1_FinishedTrackShape event will fire – here you will add the map shape and record any data in a data store (for example, storing the latitude and longitude in a database).

The following code should make it clear:

C#

// Put this code in the form's load event. This will show a map of the world.

Map1.MapUnit = MapLengthUnits.DecimalDegrees;

Layer worldLayer = new Layer(@"..\..\SampleData\world\cntry02.shp", true);

worldLayer.ZoomLevel01.GeoStyle = GeoAreaStyles.GetSimpleAreaStyle(GeoColor.KnownColors.LightGray,GeoColor.KnownColors.Black);

worldLayer.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.ZoomLevel18;

 

Map1.Layers.Add(worldLayer);

 

// Then, set the map's mode to track point so that every time the user clicks, a point shape will be created

Map1.Mode = ModeType.TrackPoint;

 

//Finally, in the FinishedTrackShape event, add the code to add the point to the map as a map shape.

private void Map1_FinishedTrackShape(BaseShape Shape)

{

BasePointShape pnt = (BasePointShape)Shape;

Map1.MapShapes.Add(new PointMapShape(pnt));

 

// Here you would also add any logic to store the location of the point the user selected

}

VB.NET

' Put this code in the form's load event. This will show a map of the world.

Map1.MapUnit = MapLengthUnits.DecimalDegrees

Dim worldLayer As New Layer("..\..\SampleData\world\cntry02.shp", True)

worldLayer.ZoomLevel01.GeoStyle = GeoAreaStyles.GetSimpleAreaStyle(GeoColor.KnownColors.LightGray, GeoColor.KnownColors.Black)

worldLayer.ZoomLevel01.ApplyUntilZoomLevel = ApplyUntilZoomLevel.ZoomLevel18

 

Map1.Layers.Add(worldLayer)

 

' Then, set the map's mode to track point so that every time the user clicks, a point shape will be created

Map1.Mode = ModeType.TrackPoint


'Finally, in the FinishedTrackShape event, add the code to add the point to the map as a map shape.

Private Sub Map1_FinishedTrackShape(ByVal Shape As BaseShape)

Dim pnt As BasePointShape = CType(Shape, BasePointShape)

Map1.MapShapes.Add(New PointMapShape(pnt))

 

' Here you would also add any logic to store the location of the point

the user selected

End Sub 

As you can see, there is very little code to actually add a map shape to a map (two lines). Most of the code will depend on how you want to store the data about the points the user selected.

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How can I define my own custom labeling plug-in?

The Rendering sample named "Custom Labeler" goes over this is greater detail but what you will need to do is create a class that inherits from MapSuite.ILabeler. There are several methods to implement, all named DrawLabels (taking in different parameters). In the sample, you will see DrawLabels implemented for Polygons and MultiLines. The code for polygons is below:

C#

// Class declaration
public class CustomLabeler : MapSuite.ILabeler

{

// DrawLabels routine

public void DrawLabels(Graphics g, Array[] TextSymbolArrays, Array[] SymbolArray, MapSuite.Geometry.PolygonF[] Polygons, ref SimplePolygonF[] LabeledAreas, int CanvasWidth, int CanvasHeight)

{

// Drawing labels for polygons

StringFormat Format = new StringFormat();

Format.Alignment = StringAlignment.Center;

for (int i = 0; i <= Polygons.Length - 1; i++)

{

TextSymbol[] TextSymbols = (TextSymbol[])TextSymbolArrays[i];

for (int j = 0; j <= Polygons[i].Parts.Length - 1; j++)

{

for (int k = 0; k <= TextSymbols.Length - 1; k++)

{

g.DrawString(TextSymbols[k].TextValue, TextSymbols[k].Font, TextSymbols[k].Brush, Polygons[i].Parts[j].Centroid.X + TextSymbols[k].XOffset, Polygons[i].Parts[j].Centroid.Y + TextSymbols[k].YOffset, Format);

}

}

}

}

 

 

 

public void DrawLabels(Graphics g, Array[] TextSymbolArrays, Array[] SymbolArrays, PointF[] Points, ref SimplePolygonF[] LabeledAreas, Int32 CanvasWidth, Int32 CanvasHeight)

{

// This routine left blank intentionally.

}

 

public void DrawLabels(Graphics g, Array[] TextSymbolArrays, Array[] SymbolArrays, MultiPointF[] MultiPoints, ref SimplePolygonF[] LabeledAreas, Int32 CanvasWidth, Int32 CanvasHeight)

{

// This routine left blank intentionally.

}

 

public void DrawLabels(Graphics g, Array[] TextSymbolArrays, Array[] SymbolArrays, MultiLineF[] MultiLines, ref SimplePolygonF[] LabeledAreas, Int32 CanvasWidth, Int32 CanvasHeight)

{

// This routine left blank intentionally.

}

} 

VB.NET

' Class declaration

Public Class CustomLabeler

Implements MapSuite.ILabeler

 

' DrawLabels routine

Public Sub DrawLabels(ByVal g As Graphics, ByVal TextSymbolArrays As Array(), ByVal SymbolArray As Array(), ByVal Polygons As MapSuite.Geometry.PolygonF(), ByRef LabeledAreas As SimplePolygonF(), ByVal CanvasWidth As Integer, ByVal CanvasHeight As Integer) Implements ILabeler.DrawLabels

' Drawing labels for polygons

Dim Format As New StringFormat()

Format.Alignment = StringAlignment.Center

For i As Integer = 0 To Polygons.Length - 1

Dim TextSymbols As TextSymbol() = DirectCast(TextSymbolArrays(i), TextSymbol())

For j As Integer = 0 To Polygons(i).Parts.Length - 1

For k As Integer = 0 To TextSymbols.Length - 1

g.DrawString(TextSymbols(k).TextValue, TextSymbols(k).Font, TextSymbols(k).Brush, Polygons(i).Parts(j).Centroid.X + TextSymbols(k).XOffset, Polygons(i).Parts(j).Centroid.Y + TextSymbols(k).YOffset, Format)

Next

Next

Next

End Sub

 

 

 

Public Sub DrawLabels(ByVal g As Graphics, ByVal TextSymbolArrays As Array(), ByVal SymbolArrays As Array(), ByVal Points As PointF(), ByRef LabeledAreas As SimplePolygonF(), ByVal CanvasWidth As Int32, ByVal CanvasHeight As Int32) Implements ILabeler.DrawLabels

' This routine left blank intentionally.

End Sub

 

Public Sub DrawLabels(ByVal g As Graphics, ByVal TextSymbolArrays As Array(), ByVal SymbolArrays As Array(), ByVal MultiPoints As MultiPointF(), ByRef LabeledAreas As SimplePolygonF(), ByVal CanvasWidth As Int32, ByVal CanvasHeight As Int32) Implements ILabeler.DrawLabels

' This routine left blank intentionally.

End Sub

 

Public Sub DrawLabels(ByVal g As Graphics, ByVal TextSymbolArrays As Array(), ByVal SymbolArrays As Array(), ByVal MultiLines As MultiLineF(), ByRef LabeledAreas As SimplePolygonF(), ByVal CanvasWidth As Int32, ByVal CanvasHeight As Int32) Implements ILabeler.DrawLabels

' This routine left blank intentionally.

End Sub

End Class 

Now, to use your custom labeler, you just need to create it and plug it in. Like the following:

C#

CustomLabeler cl = new CustomLabeler();
customZoomLevel.LabelerPlugin = cl; // this assumes you have a zoomlevel object declared as customZoomLevel

VB.NET

Dim cl As New CustomLabeler()
customZoomLevel.LabelerPlugin = cl '-- this assumes you have a zoomlevel object declared as customZoomLevel

 

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Can I change the data in a shape file, and if so, how?

Yes, you can. To delete shapes in the file, use the Layer.DeleteShape method which takes in a record number. If you want to change the data in a shape file, first you must call Layer.BeginEdit and then follow that with either Layer.CommitEdit or Layer.RollbackEdit. Between calling BeingEdit and CommitEdit or RollbackEdit you can call Layer.DeleteShape, Layer.AddShape, or Layer.UpdateShape depending on whether you want to do a delete, insert, or an update. The Layer sample named "Edit Shape File" is the sample that best illustrates this but below you will see some code that will help you.

C#

// Insert a new shape
private void Map1_FinishedTrackShape(MapSuite.Geometry.BaseShape Shape)
{
 Map1.Layers[0].BeginEdit();

Map1.Layers[0].AddShape(Shape);

Map1.Layers[0].CommitEdit();
}

// Update an existing shape
private void Map1_FinishedTrackShape(MapSuite.Geometry.BaseShape Shape)
{
Map1.Layers[0].BeginEdit();

Map1.Layers[0].UpdateShape(Convert.ToInt32(lblRecordNumber.Text), Shape);

Map1.Layers[0].CommitEdit();
}

// Delete an existing shape
Map1.Layers[0].BeginEdit();

Map1.Layers[0].DeleteShape(Convert.ToInt32(lblRecordNumber.Text));

Map1.Layers[0].CommitEdit();

VB.NET

' Insert a new shape

Private Sub Map1_FinishedTrackShape(ByVal Shape As MapSuite.Geometry.BaseShape)

Map1.Layers(0).BeginEdit()

Map1.Layers(0).AddShape(Shape)

Map1.Layers(0).CommitEdit()

End Sub

 

' Update an existing shape

Private Sub Map1_FinishedTrackShape(ByVal Shape As MapSuite.Geometry.BaseShape)

Map1.Layers(0).BeginEdit()

Map1.Layers(0).UpdateShape(Convert.ToInt32(lblRecordNumber.Text), Shape)

Map1.Layers(0).CommitEdit()

End Sub

'-- Delete an existing shape
Map1.Layers(0).BeginEdit()

Map1.Layers(0).DeleteShape(Convert.ToInt32(lblRecordNumber.Text))

Map1.Layers(0).CommitEdit()

Back to Top

How can I stop one or more map shapes from being printed while printing the map?

The easiest way would be to set each map shape's Active property to false. If Active is true then the map shape will print, otherwise it will not. You can use this to stop just a few map shapes from printing or you could loop through the collection and stop them all from printing. The following code should help make it clear for you.

C#

// User clicks on something to trigger the printing of the map

PrintPreviewDialog print = new PrintPreviewDialog();

Map1.MapShapes[0].Active = false;

print.Document = Map1.PrintDocument;

print.ShowDialog();

VB.NET

'User clicks on something to trigger the printing of the map

Dim print As New PrintPreviewDialog()

map1.MapShapes.Item(0).Active = False

print.Document = map1.PrintDocument

print.ShowDialog()

Now, the first map shape will not show in the print preview dialog. You could also put that one line inside of a loop and affect all the map shapes.

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What do I need to do to distribute my application which uses Map Suite? How do I get all the dependencies on the destination computer?

In the full version of Map Suite, we include a merge module that can be included in your setup program. The merge module will install everything needed for Map Suite to run on that machine.

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What vector and raster formats are supported by Map Suite?

For vector data, Map Suite supports ShapeFile format.
For raster imagery, Map Suite supports TIFF, GeoTIFF, MrSID, ECW, JPEG2000, BMP and JPEG.

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How do I zoom in to a Point?

Zooming into a point is a common question we receive from our customers. Since point-based objects don't consume much area, it can be a bit difficult to create an extent to zoom in to. The answer to this problem is the buffer method. The buffer method allows you to buffer a point by a certain distance to give it area. For example, in the code below we have taken a point and buffered it by 5 miles on each side. Once we have this new buffered point, all we need to do is get the RectangleR from the envelope and set this to the map extent. This will then zoom the map into an area 10 miles around your point. Below is some sample code to help get you started:

C#

// The following code will zoom the map into an area 10 miles around the point.
PointShape pnt = new PointShape(LongValue, LatValue);

Map1.CurrentExtent = pnt.Buffer(5, MapLengthUnits.DecimalDegrees, MapLengthUnits.miles).Envelope.ToRectangleR();

VB.NET

' The following will zoom the map into an area 10 miles around the point.
Dim pnt As PointShape = New PointShape(LongValue, LatValue)
Map1.CurrentExtent = pnt.Buffer(5, MapLengthUnits.DecimalDegrees, MapLengthUnits.miles).Envelope.ToRectangleR

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How do I zoom in to a set of MapShape Points?

To zoom the map in to an extent that includes specific points see the following routine:

C#

private RectangleR CalculateMapExtent()

{

//Declare Variables

PointShape pointShape;

double upperLeftLat = 0;

double upperLeftLong = 0;

double lowerRightLat = 0;

double lowerRightLong = 0;

 

//Loop through the points collection to find the upper left and lower right point values

foreach (BaseMapShape baseMapShape in Map1.MapShapes)

{

if (baseMapShape is PointMapShape)

{

pointShape = (PointShape)baseMapShape.BaseShape;

if (pointShape.Y > upperLeftLat | upperLeftLat == 0) upperLeftLat = pointShape.Y;

if (pointShape.X < upperLeftLong | upperLeftLong == 0) upperLeftLong = pointShape.X;

if (pointShape.Y < lowerRightLat | lowerRightLat == 0) lowerRightLat = pointShape.Y;

if (pointShape.X > lowerRightLong | lowerRightLong == 0) lowerRightLong = pointShape.X;

}

}

//Create variables to set the extent

PointR upperLeftPoint = new PointR(upperLeftLong, upperLeftLat);

PointR lowerRightPoint = new PointR(lowerRightLong, lowerRightLat);

RectangleR mapExtent = new RectangleR(upperLeftPoint, lowerRightPoint);

//Scale Up Map extent by 5%

mapExtent.ScaleUp(5);

if (mapExtent.get_Width(MapLengthUnits.DecimalDegrees, MapLengthUnits.miles) < 400)

{

while (!(mapExtent.get_Width(MapLengthUnits.DecimalDegrees, MapLengthUnits.miles) > 400))

{

mapExtent.ScaleUp(5);

}

}

return mapExtent;

}

VB.NET

Private Function CalculateMapExtent() As RectangleR

'Declare Variables

Dim baseMapShape As BaseMapShape

Dim pointShape As PointShape

Dim upperLeftLat As Double

Dim upperLeftLong As Double