check if the element exists in javascript

var element = document.getElementById("test");
    //If it isn't "undefined" and it isn't "null", then it exists.
if(typeof(element) != 'undefined' && element != null){
    alert('Element exists');
} else{
	alert('Element does not exist');
}
 var myEle = document.getElementById("myElement");
    if(myEle){
        var myEleValue= myEle.value;
    }
<div id="test">Example DIV element.</div>
 
<script>
    //Attempt to get the element using document.getElementById
    var element = document.getElementById("test");
 
    //If it isn't "undefined" and it isn't "null", then it exists.
    if(typeof(element) != 'undefined' && element != null){
        alert('Element exists!');
    } else{
        alert('Element does not exist!');
    }
</script>