将字符串转换为js数组

Question

I am probably doing a very small and fundamental mistake here. I am getting some information in the dom which exactly looks like this

<span id="pids" style="display:none">["26551826","22956811","22959266"]</span>

Which then I am trying to convert into a js array. For that I am doing this

var x = document.getElementById('pids');
var y = eval(x);

alert(y.length);

And the result is undefined. What am I doing wrong here?

Here is my fiddle

http://jsfiddle.net/sghoush1/sbrmT/2/

Answer 1

Try this : http://jsfiddle.net/sbrmT/3/

var x = document.getElementById('pids').innerText; //you need to get the value
var y = JSON.parse(x); //dont use eval , json.parse will do.

alert(y.length);

Answer 2

尝试这个 -

var x = document.getElementById('pids').innerHTML;

Answer 3

http://jsfiddle.net/8vS2D/

var x = document.getElementById('pids');
var y = eval(x);

alert(eval(x.innerText));