I have the following code
<span id="X1a">
<script>
document.getElementById("X1").innerHTML = 'Output1'
document.getElementById("X2").innerHTML = 'Output2'
<!---etc - several more similar lines for Outputx-->
</script>
What I want to do is to be able to input (or select) the value to put in the id= line. So i can choose to print X1 or X2 or Xx. How can I do that?
you can use setAttribute() to change the value id.
example
document.getElementById("id").setAttribute("id", "X1")
or you can read reference in w3school
https://www.w3schools.com/jsref/met_element_setattribute.asp