In the last days, many customers who are in the process of porting their TX Text Control ActiveX applications to .NET have asked me how to merge different files into one document.

In the TX Text Control ActiveX, there was a parameter (CurSelection) in the Load method which specifies, whether the loaded document replaces the content or whether it should be appended.

In TX Text Control .NET for Windows Forms, there is no such parameter, but a new class: the Selection class.

This class can be used to manipulate the currently selected text. Additionally, this class contains a Load and Save method to load documents into a selection or to save only the selected text: