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RichTextBox.SelectionAlignment Property

Gets or sets the alignment to apply to the current selection or insertion point.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public HorizontalAlignment SelectionAlignment { get; set; }


The specified value is not one of the values defined in the HorizontalAlignment class.

If no paragraph is selected in the control, setting this property applies the alignment setting to the paragraph in which the insertion point appears as well as to paragraphs created after the paragraph that has the alignment property setting. For example, if there are two paragraphs in a RichTextBox control and the insertion point is located within the second paragraph. If you set the SelectionAlignment property to HorizontalAlignment.Center, the paragraph at the insertion point will be centered within the control. If a third paragraph is created after the second paragraph, it also is aligned to the center of the control.

If a selection is made within the control when the property is set, all paragraphs selected are aligned based on this property setting. You can use this property to align the paragraphs in a document being created in the RichTextBox. For example, if you want all paragraphs in a document to be centered, you can select all the paragraphs in the control and set the SelectionAlignment property to HorizontalAlignment.Center.


SelectionAlignment returns SelectionAlignment.Left when the text selection contains multiple paragraphs with mixed alignment.

The following code example demonstrates how to align text within the RichTextBox. This example requires that a RichTextBox control, named richTextBox1, has been added to the form.

private void WriteCenteredTextToRichTextBox()
   // Clear all text from the RichTextBox;
   // Set the foreground color of the text.
   richTextBox1.ForeColor = Color.Red;
   // Set the alignment of the text that follows.
   richTextBox1.SelectionAlignment = HorizontalAlignment.Center;
   // Set the font for the text.
   richTextBox1.SelectionFont = new Font("Lucinda Console", 12);
   // Set the text within the control.
   richTextBox1.SelectedText = "This text is centered using the SelectionAlignment property.\n";

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.