.NET Windows Forms in a Nutshell

Name

RichTextBox

Synopsis

This Control, derived from TextBoxBase, extends the basic text box functionality to include character and paragraph formatting. It can also display embedded objects such as images, all with an arbitrary ZoomFactor and optional ScrollBars.

Content can be assigned with the standard Text property and AppendText() methods. In addition to these TextBoxBase methods, LoadFile() will bring plain ASCII text or an RTF file into the control. Alternatively, you can assign formatted Rtf markup directly. If the content contains embedded objects, the string obtained from the Text property will include a placeholder character for each such item. The content can be saved to a file as either ASCII or RTF markup using the SaveFile() method.

Once you have some text in the control, you can begin to manipulate it. First, some of this content must be selected, either by the user, or programmatically. To assist the user, you can enable the AutoWordSelection property. This provides the highlight-completion behavior seen in Microsoft WordPad: if you double-click or select a portion of a word, the entire word will be highlighted. You can get and set the SelectionStart and the SelectionLength independently, or set both at once with the Select() or SelectAll() methods. If the SelectionLength is 0, the SelectionStart represents the position of the caret. ScrollToCaret() ensures that the current cursor position is visible on screen.

You can also get the SelectionType. This returns a combination ...