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The RadSyntaxEditor control supports not only selection via the UI but also exposes API to work with the selection programmatically. In addition, the selection can be controlled via the keyboard by a number of key combinations. You can also disable selection in the control if your business scenario demands it.

UI Selection

The user is able to select the content inside RadSyntaxEditor in the same way as in Visual Studio. This is done by clicking on the desired position and dragging to the desired end of the selection.

Figure 1: RadSyntaxEditor with selected text


The UI selection is enabled by default. To enable or disable it use the IsSelectionEnabled property

Enable/Disable selection

this.radSyntaxEditor1.IsSelectionEnabled = true;

Me.RadSyntaxEditor1.IsSelectionEnabled = True

Keyboard Combinations

Users can also select text by using their keyboard. Here's a list of the supported key combinations.

Table 1: Hotkeys supported by the RadSyntaxEditor and their actions

Hotkeys Action
Shift + Right arrow Extends selection one position forward.
Shift + Left arrow Extends selection one position backward.
Shift + Up arrow Extends selection to the same position on the previous line.
Shift + Down arrow Extends selection to the same position on the next line.
Shift + Home Extends selection to the start of the current line.
Shift + End Extends selection to the end of the current line.
Ctrl + Shift + Left arrow Extends selection to the current word start position.
Ctrl + Shift + Right arrow Extends selection to the current word end position.
Ctrl + A Selects the entire document.

Customize the Selection

You can modify the appearance of the selection in the control through the SelectionFill and SelectionStroke properties of RadSyntaxEditor.

Customize the appearance of the selection

this.radSyntaxEditor1.SyntaxEditorElement.SelectionFill = new SolidBrush(Color.FromArgb(95, Color.Red));
this.radSyntaxEditor1.SyntaxEditorElement.SelectionStroke = new SolidBrush(Color.DarkRed);

Me.RadSyntaxEditor1.SyntaxEditorElement.SelectionFill = New SolidBrush(Color.FromArgb(95, Color.Red))
Me.RadSyntaxEditor1.SyntaxEditorElement.SelectionStroke = New SolidBrush(Color.DarkRed)

Figure 2: RadSyntaxEditor with custom selection color


Programmatic Selection

Through the control's Selection property, you can programmatically manipulate the selection and get additional details for the selected span(s). The following example demonstrates how you can get the entire selection as a string through the GetSelectedText method.

string selectedText = this.radSyntaxEditor1.SyntaxEditorElement.Selection.GetSelectedText();

Dim selectedText As String = Me.RadSyntaxEditor1.SyntaxEditorElement.Selection.GetSelectedText()

See Also

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