In TX Text Control, a document consists of separate text areas such as main text, headers, footers and text frames. Each of these areas have their own collections for contained elements such as lines, images, fields or the TXTextControl.Selection class object.

In order to manipulate the text in a TXTextControl.HeaderFooter class object, you would need to access the TXTextControl.HeaderFooter.Selection property. To manipulate text in all headers and footers, you would need to loop through all available objects.

To avoid that, we implemented the "meta" collection TXTextControl.TextPartCollection class. An instance of this class contains all text parts in a TX Text Control document. Each text part of a document is implemented as an IFormattedText interface. The IFormattedText interface contains properties and methods common to all text parts in a TX Text Control document.

In order to set text to the beginning of each text part in the complete document, the following code can be used:

foreach (IFormattedText ftTextPart in textControl1.TextParts)
{
    ftTextPart.Selection.Start = 0;
    ftTextPart.Selection.Text = "TX Text Control";
}

This method is very handy to access all ApplicationFields in a document:

foreach (IFormattedText ftTextPart in textControl1.TextParts)
{
    foreach (ApplicationField field in ftTextPart.ApplicationFields)
    {
        field.Text = "Test";
    }
}