Find and Replace Placeholders in a Word Template

We have a template file that we use as a baseline in our report generation (see here for help creating a new Word document from a template). The template file has some placeholders for title, subtitle, author, etc. I wanted to be able to dynamically replace those with content when the rest of the document was generated. This took me way longer than I expected to figure out so here is hopefully some info to help the next person. First I found the relevant section in the XML (the Open XML Productivity Tools are a great help for this).

<w:sdt>   <w:sdtPr>     <w:rPr>       <w:sz w:val="96" />       <w:szCs w:val="96" />     </w:rPr>     <w:alias w:val="Title" />     <w:tag w:val="" />     <w:text />   </w:sdtPr>   <w:sdtEndPr />   <w:sdtContent>     <w:r w:rsidR="00981BCE">       <w:rPr>         <w:sz w:val="96" />         <w:szCs w:val="96" />       </w:rPr>       <w:t>[Document title]</w:t>     </w:r>   </w:sdtContent> </w:sdt>

Then with a bunch of trial and error I figured out how to find and replace the '[Document title]' placeholder.

// MainDocumentPart, root Document and Body already exist just access them var mainPart = wordDocument.MainDocumentPart; var document = mainPart.Document; var body = document.Body;   // Find all of <w:sdt> elements foreach (var sdtRun in body.Descendants<SdtRun>()) {     // Look for the Title placeholder.     var alias = sdtRun.Descendants().OfType<SdtAlias>().First();     if (alias != null && alias.Val == "Title") {         //replace Title placeholder         var content = sdtRun.GetFirstChild<SdtContentRun>();         var run = content.GetFirstChild<Run>();         var text = run.GetFirstChild<Text>();         text.Text = "Report Title";     } }