If this property returns an empty string (""), there is no operation available to reapply to the control. You can use this method to determine the last action undone in the RichTextBox control that can then be reapplied to the control when a call to the Redo method is made. You can determine whether there are any operations to be reapplied to the control by using the CanRedo property.
The following code example demonstrates how to use the CanRedo and RedoActionName properties, and the Redo method, to restrict a redo operation to any action except the deletion of text. This example requires that you have a form that contains a RichTextBox control and that an operation within the RichTextBox has been performed and undone before the code in this example is called.
// Determines if a Redo operation can be performed. if(richTextBox1.CanRedo == true)
// Determines if the redo operation deletes text. if (richTextBox1.RedoActionName != "Delete")
// Perform the redo.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)