c# Word Interop - Setting paragraph indentation

Question

I have a requirement to programatically (in C#) either switch on or off the hanging indent of a particular paragraph.

I have created an add in, with a button that when clicked, executes code where I (attempt) to do this. Its a toggle, so first click adds the Hanging indent and second click should remove it.

In word, its the setting in Paragraph>Indentation, followed by the setting "Special" equal to None or Hanging.

My best attempt at this is with the following code:

foreach (Footnote rngWord in Globals.OSAXWord.Application.ActiveDocument.Content.Footnotes)
    rngWord.Range.ParagraphFormat.TabHangingIndent(
        rngWord.Range.ParagraphFormat.FirstLineIndent == 0 ? 1 : -1);

It ONLY amends the last line in the paragraph for some reason. I need it to be all lines which hang except the very first. What am I doing wrong?

Modifications:

Note - I'm actually performing this on footnotes in my document.

Answer 1

For anyone who may happen to come across this - here's how I resolved:

try
{
    // Loop through each footnote in the word doc.
    foreach (Footnote rngWord in Microsoft.Office.Interop.Word.Application.ActiveDocument.Content.Footnotes)
    {
        // For each paragraph in the footnote - set the indentation.
        foreach (Paragraph parag in rngWord.Range.Paragraphs)
        {
            // If this was not previously indented (i.e. FirstLineIndent is zero), then indent.
            if (parag.Range.ParagraphFormat.FirstLineIndent == 0)
            {
                // Set hanging indent.
                rngWord.Range.ParagraphFormat.TabHangingIndent(1);
            }
            else
            {
                // Remove hanging indent.
                rngWord.Range.ParagraphFormat.TabHangingIndent(-1);
            }
        }
    }
    // Force the screen to refresh so we see the changes.
    Microsoft.Office.Interop.Word.Application.ScreenRefresh();

}
catch (Exception ex)
{
    // Catch any exception and swollow it (i.e. do nothing with it).
    //MessageBox.Show(ex.Message);
}