title: Attempting to get internal SheetId in VSTO for assistance in detecting a sheet rename
body: <p>I am currently caching information for formulas on sheets within my addin. When there is a change on the sheet this is captured so that the cache is updated. I have seen that there is no reliable way though to detect when the sheet name is changed so I did some work to see what changed when tabs are added, moved, etc.</p>
  
  <p>In making my workbook at .zip file and looking at workbook.xml, I have found the following structure:</p>
  
  <pre><code>&lt;sheets&gt;
     &lt;sheet r:id="rId1" sheetId="2" name="POC2"/&gt;
     &lt;sheet r:id="rId2" sheetId="1" name="POC1"/&gt;
  &lt;/sheets&gt;
  </code></pre>
  
  <p>Is there anything that I am missing or does this approach seem solid?</p>
  
  <p>The sheetId seems to be available and not be influenced by changing tab order and other operations. My thought is that I can use this internal id along with the sheet name. If the sheetId has a different name than what is in the cache, it would mean the sheet was renamed. If the sheetId no longer exists, the sheet was deleted, etc.</p>
  
  <p>My question is if there is a way in VSTO to get hold of the sheetId attribute if my other ideas are valid.</p>
  
  <p>Thanks,</p>
  
  <p>Lee</p>