How to compare events in JavaScript

Question

I want to give document onkeydown & onkeyup in same function

How to know which event that trigger the function ?

<script>

document.onkeydown = listener;
document.onkeyup = listener;

function listener(e) {

 if(e === "onkeydown"){
    console.log("onkeydown");
 }

 else if(e === "onkeyup "){
    console.log("onkeyup ");
 }

 else{
    console.log("unknown");
 }
}

</script>

Answer 1

You can use e.type

document.onkeydown = listener; document.onkeyup = listener;

function listener(e) {

 if(e.type === "keydown"){
    console.log("keydown");
 }

 else if(e.type === "keyup "){
    console.log("keyup ");
 }

 else{
    console.log("unknown");
 }
}

Answer 2

You can use e.type but remove the on prefix.

function listener(e) {
   if(e.type.indexOf("key") !== 1)
      console.log("onkey" + (e.type == "keydown" ? "down" : "up")); 
   else { console.log("unknown"); }
}