Pitney Bowes MapXtreme - Manual (Page 212)

Chapter 10: Creating Expressions
Expression Examples
MapXtreme v7.1 219 Developer Guide
MapInfo.Engine.Session.Current.Catalog.Search("uscty_1k", si)
' Set the map view to show search results
MapInfo.Engine.Session.Current.MapFactory(0).SetView(fc.Envelope)
' Set the view of the first map.
' Add results to selection.
MapInfo.Engine.Session.Current.Selections.DefaultSelection.Add(fc)
End Sub
For more information on the Feature class and search methods, see Features and Feature
Collections .
Thematic Expression Example
A pie theme is an object theme that draws a pie chart based on the numeric value of the theme's
expression. The expression for the theme is made up of three columns: Pop_Native",
"Pop_Asian","Pop_Other".
VB example:
Public Shared Sub MapInfo_Mapping_Thematics_PieTheme(ByVal _
map As Map)
' Load a map based on one table
map.Load(New MapTableLoader("world.tab"))
Dim lyr As FeatureLayer = CType(map.Layers("world"), FeatureLayer)
' Create a new pie theme
Dim pieTheme As MapInfo.Mapping.Thematics.PieTheme = New _
MapInfo.Mapping.Thematics.PieTheme(map, lyr.Table, "Pop_Native", _
"Pop_Asian", "Pop_Other")
' Create an object theme layer based on that pie theme
Dim thmLayer As ObjectThemeLayer = New ObjectThemeLayer("World _
Pop Growth Rate", Nothing, pieTheme)
'Add object theme to the map's layer collection.
map.Layers.Add(thmLayer)
End Sub
For more information on themes, see Chapter 14: Using Themes and Legends .
Label Expression Example using Date and Time
Expressions are properties of a label modifier which you use to modify the default properties used to
make a label. The expression in the code example says to display the label in this form:
Date/Time: .
VB example:
Public Shared Sub MapInfo_Mapping_OverrideLabelModifier(ByVal _
modifier As OverrideLabelModifier)