How to: Mark Text as Hidden and Display Hidden Text in the RichEditControl
The following example describes how to mark text as hidden and display hidden text in the RichEditControl.
#Mark Text as Hidden
Use the Range property to get the range occupied by the target text.
Refer to the How to: Select Text Programmatically example for information on how to select text in code, and the How To: Obtain Specific Document Part topic for details on how to obtain specific document part.
- Call the SubDocument.BeginUpdateCharacters method to update the character properties. Pass the retrieved range to the method as a range parameter.
- Set the CharacterPropertiesBase.Hidden property to true to hide the text.
- Call the SubDocument.EndUpdateCharacters method to finalize the update.
The code sample below hides the third document paragraph.
DocumentRange hiddenRange = richEditControl1.Document.Paragraphs[2].Range;
CharacterProperties hiddenTextProperties = richEditControl1.Document.BeginUpdateCharacters(hiddenRange);
hiddenTextProperties.Hidden = true;
richEditControl1.Document.EndUpdateCharacters(hiddenTextProperties);
#Display Hidden Text
Set the FormattingMarkVisibilityOptions.HiddenText property to RichEditFormattingMarkVisibility.Visible to display hidden text in the RichEditControl. Access the property using the richEditControl.Options.FormattingMarkVisibility notation.
richEditControl1.Options.FormattingMarkVisibility.HiddenText = RichEditFormattingMarkVisibility.Visible;
The image below illustrates how the RichEditControl displays hidden text.