Read in text from list item and place it in form text box

Hello All,

I found someones javascript example online but it does not give details.  Perhaps someone can shed some light on how I should configure this.

The field I wish to fill in on my form is called "Comment"  (this is the task list comment field)

The calculated field Name that will have the data is called "ResponseText"

The calculated field formula is : lookup("ECC Letter", "ID", ResponseTitles, "Letter")

The new example calculated field looks like:

UpdateTextBox(<Existing formula>)

The example javascript from online looks like: (* what is inpval? *Is TextBox in the example my Comment field?)

function UpdateTextBox(inpval){
   NWF$('#'+TextBox).val(inpval);
   return inpval;
}

Therefore my new calculated field looks like: 
UpdateComment(lookup("ECC Letter", "ID", ResponseTitles, "Letter"))

the javascript (this is where I am probably messing up) looks like:
function UpdateComment(ResponseText){ 
   NWF$('#'+Comment).val(ResponseText); 
   return ResponseText; 
}
*  I just get errors when previewing...


Thanks for helping

I've never done anything like his, but intermediate calculation value control doesn't seem to me to be necessary.

I would say something like this should do it directly.

NWF.FormFiller.Events.RegisterAfterReady(function () {
    NWF$('#' + jsvarResponeTitles).change(function(evt){
        NWF.RuntimeFunctions.SPLookup("ECC Letter", "ID",NWF.RuntimeFunctions.parseLookup(evt.target.value,false),'Letter').done(function(data){
             NWF$('#' + jsvarComments).val(data);
             NWF.FormFiller.Functions.ProcessOnChange(NWF$('#' + jsvarComments));   
        });
    });
});


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