javascript - If element exists in a document -

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it's possible situation function use out of date jquery element. example when use closer , callback:

    $("input").each(function () {        var input = $(this);         //here example remove input dom        //and insert new 1 input         $.ajax(url, function(){           fun(input)        }     });  function fun(input){ //do input.val('newvalue') }

questions are: how can sure reference on variable still right. , if element has been reacreated how can new reference on new input (input doesnt have id , classes)?

update1: made small update. use old input reference in function fun. , newvalue not apply new input coz current input old value.

you can check whether element exists checking length of jquery object. example: 

if($(this).length < 1) {     // element no longer exists in dom }

however, can use jquery's on() function bind events elements exist now, or in future, , perhaps that's better approach 1 you're working with. example:

$('body').on('click', 'input', function(e) {       // place click handler here. });

this article might prove worthwhile read you.


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