Field Disable/Enable for NewForm/EditForm

Field_Hide_show.js

//https://msdn.microsoft.com/en-us/library/office/dn600182.aspx#bk_FieldSetShowInNewForm
//https://msdn.microsoft.com/en-us/library/office/jj838353.aspx

//<script src="https://ajax.aspnetcdn.com/ajax/jQuery/jquery-3.2.1.min.js"></script>
//<script>
$(document).ready(function(){
	var url = "https://unicef.sharepoint.com/teams/DFAM/BudgetSection/_api/web/Lists/getByTitle('XXX')/Fields(guid'XXX')/setShowInNewForm(false)";
	$.ajax({
	  url: url,
	  contentType: "application/json;odata=verbose",
	  type: "POST",
	  headers: {
            "Accept": "application/json;odata=verbose",
	        "X-RequestDigest": $("#__REQUESTDIGEST").val()
	    },
	  success: successHandler,
	  error: errorHandler
	});
	
	function successHandler(data,message,response){
		console.log(data);
		console.log(message);
		console.log(response);
	}
	
	function errorHandler(a,b,c){
		console.log(a);
		console.log(b);
		console.log(c);
	}
});
//</script>