Aug 202012
 

This is something I threw together when having to relink a couple dozen InfoPath 
libraries all containing 100-1000
forms. Why Microsoft doesn't have a check all button at the top of the page is 
beyond me. Here it is...
1) Open the library. Click Settings -> Form Library Settings -> Relink documents to 
this Library
2) Open this page in SharePoint designer.
3) Add this to the top of the page after the <Form> tag.
<script type="text/javascript" language="javascript"> 
function CheckAll(chk) { 
for (i = 0; i < chk.length; i++) 
chk[i].checked = true ; 
} 
</script>
<input type="button" value="Check All" onclick="CheckAll(document.aspnetForm.chkRepair)" > 

Save, Refresh the page, click and thank me :)! 

Another TIP: Instead of modding the page with SharePoint Designer. Just add Content 
Editor to the top of the page (via Site Actions -> Edit Page). Drop in the 
JavaScript from above, and save the page.
The JavaScript stilled worked great for me in IE9.
Source