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I'm pretty confused with the behaviour of arrays of strings when I loop them through the jQuery.each() method. Apparently, the strings become jQuery objects inside the callback function. However, I cannot use the this.get() method to obtain the original string; doing so triggers a this.get is not a function error message. I suppose the reason is that it's not a DOM node. I can do $(this).get() but it makes my string become an array (from "foo" to ["f", "o", "o"]).

How can I cast it back to string? I need to get a variable of String type because I pass it to other functions that compare the values among them.

I enclose a self-contained test case (requires Firebug's console):

<!DOCTYPE html>
<html>
<head><title></title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type="text/javascript"><!--
$(function(){
    var foo = [];
    var $foo = $(foo);

    foo.push("987");
    $foo.push("987");

    foo.push("654");
    $foo.push("654");

    $.each(foo, function(i){
        console.log("foo[%d]: object=%o; value=%s; string=%o", i, this, this, $(this).get()); // this.get() does not exist
    });
    $foo.each(function(i){
        console.log("$foo[%d]: object=%o; value=%s; string=%o", i, this, this, $(this).get()); // this.get() does not exist
    });
});
//--></script>
</head>
<body>

</body>
</html>
Álvaro González
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    I just experienced the same issue, however found out that this works as expected in strict mode. – Joost Jan 12 '16 at 11:57

2 Answers2

13

edit/clarification: calllback functions takes two arguments, the second one is value of the variable. Use it instead of this I have tested both variants and everything seems to work as expected (strings are still strings).

>>> $.each(['foo','bar'], function(i, s){ console.info( s, typeof s ) })
foo string
bar string

>>> $(['foo','bar']).each(function(i, s){ console.info( s, typeof s ) })
foo string
bar string
pawel
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    `this` is not a jQuery object when looping through strings, it wraps the string in a `String` object. If you do `this.toString()` you will get a regular string. – David Hellsing Nov 23 '12 at 13:47
3

This works in my Firefox 3.5:

$(function(){
    var foo = [];

    foo.push("abc");
    foo.push("def");

    $.each(foo, function(i){
        console.log(typeof ("" + this)); 
        });
});

The console shows

string
string
balpha
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