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Check if a div does NOT exist with javascript

Checking if a div exists is fairly simple

if(document.getif(document.getElementById('if')){

}

But how can I check if a div with the given id does not exist?

var myElem = document.getElementById('myElementId');
if (myElem === null) alert('does not exist!');
if (!document.getElementById("given-id")) {
//It does not exist
}

The statement document.getElementById("given-id") returns null if an element with given-id doesn't exist, and null is falsy meaning that it translates to false when evaluated in an if-statement. ( other falsy values )

Try getting the element with the ID and check if the return value is null:

document.getElementById('some_nonexistent_id') === null

If you're using jQuery, you can do:

$('#some_nonexistent_id').length === 0

Check both my JavaScript and JQuery code :

JavaScript:

if (!document.getElementById('MyElementId')){
    alert('Does not exist!');
}

JQuery:

if (!$("#MyElementId").length){
    alert('Does not exist!');
}

如果没有这样的元素,则getElementById返回null

That works with :

 var element = document.getElementById('myElem');
 if (typeof (element) != undefined && typeof (element) != null && typeof (element) != 'undefined') {
     console.log('element exists');
 }
 else{
     console.log('element NOT exists');
 }

There's an even better solution. You don't even need to check if the element returns null . You can simply do this:

if (document.getElementById('elementId')) {
  console.log('exists')
}

That code will only log exists to console if the element actually exists in the DOM.

I do below and check if id exist and execute function if exist.

var divIDVar = $('#divID').length;
if (divIDVar === 0){ 
    console.log('No DIV Exist'); 
} else{  
    FNCsomefunction(); 
}   

All these answers do NOT take into account that you asked specifically about a DIV element.

document.querySelector("div#the-div-id")

@see https://developer.mozilla.org/en-US/docs/Web/API/Document/querySelector

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