Passing GCLID and MSCKLID to Gravity Form form values – WordPress

I’m trying to capture the GCLID and MSCKLID values from the URL, and pass them into the appropriate GF form fields. I found a way to pull them from the url, but I’m running into the DRY thing when trying to pass them into their field values.

Code that pulls them from the URL:

function getUrlVars() {
     var vars = {};
     var parts = window.location.href.replace(/[?&]+([^=&]+)=([^&]*)/gi,    
     function(m,key,value) {
        vars[key] = value;
        console.log(value);
     });
     return vars;
}
var gclid = getUrlVars()["gclid"];
var mscklid = getUrlVars()["mscklid"];

Then this is the way I’m trying to pass them into the field values currently:

var selectorGCLID = "input[name='input_25']";
var selectorMSCKLID = "input[name='input_31']";
var fieldGCLID = document.querySelector(selectorGCLID);
var fieldMSCKLID = document.querySelector(selectorMSCKLID);
if(fieldGCLID) { fieldGCLID.value = gclid; }
if(fieldMSCKLID) { fieldMSCKLID.value = mscklid; }

What’s a way where I can just check to see if the field selector is GCLID or MSCKLID, and then pass it to the appropriate field, instead of doing it 1×1 like this?