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I have a JSON code inside a textarea and I want to get it and work with it as it is exist in my website.

This is the textarea code :

<textarea>
  var settings = [
            "id" : "post_thumbnail",
            "name" : "Default Post Thumbnail",
            "desc" : "The image src that you want to use for non-thumbnail posts.", 
            "type" : "text",
            "std" : "http://lorempixel.com/640/300/"
</textarea>
I tried this but unfortunately it work only if the code exist in the website not in textarea because I get this error : 
Uncaught ReferenceError: settings is not defined
for( var i = 0; i < settings.length; i++){
        var setting_id = settings[i].id,
            setting_name = settings[i].name,
            setting_desc = settings[i].desc,
            setting_type = settings[i].type,
            setting_std = settings[i].std;
$('body').html(setting_id +'<br>'+ setting_name +'<br>'+ setting_desc +'<br>'+ setting_type +'<br>'+  setting_std);
This is a live demo : http://jsfiddle.net/tauv0or1/
                That is not JSON, it is JavaScript. Admittedly, if you remove the = and everything before it than what is left is JSON.
– Quentin
                Aug 20, 2015 at 14:52
                @Quentin Thanks for your reply. Excuse me I'm a biginner and I thought that we call this JSON. So what can I do to get what I want ?
– masked magician
                Aug 20, 2015 at 14:55
The value of textarea does not get parsed as JavaScript. Instead, change the value to valid JSON:
<textarea>
            "id" : "post_thumbnail",
            "name" : "Default Post Thumbnail",
            "desc" : "The image src that you want to use for non-thumbnail posts.", 
            "type" : "text",
            "std" : "http://lorempixel.com/640/300/"
</textarea>
And tweak your JavaScript to use JSON.parse on the value:
var field = document.getElementById("the_textarea");
var settings = JSON.parse(field.value);
Because the user can enter arbitrary information into the textarea, you might want to wrap JSON.parse in a try-catch block, and alert the user to a syntax error:
var settings = null;
try {
    settings = JSON.parse(field.value);
catch (error) {
    if (error instanceof SyntaxError) {
        alert("There was a syntax error. Please correct it and try again: " + error.message);
    else {
        throw error;
You need to eval the text first to actually run it as javascript:
eval($('textarea').text());
http://jsfiddle.net/tauv0or1/1/
Alternatively, you can parse it as JSON, but you need to edit the contents of the textarea first:
var settings = JSON.parse($('textarea').text());
http://jsfiddle.net/tauv0or1/2/
                Could a downvoter please explain? eval() is scary and bad, but it's actually the only way to evaluate the textarea content as-is.
– Paul Roub
                Aug 20, 2015 at 14:55
                @GregBurghardt eval is bad practice but it shouldn't be an automatic downvote in cases where it is a viable solution.
– James Brierley
                Aug 20, 2015 at 14:56
                @JamesBrierley: I agree that eval is not universally bad (BTW I was not the downvoter). You were merely trying to fix the OP's original issue where they wanted to parse the textarea value as-is and not change their JavaScript code -- in which case eval would work, albeit bad practice.
– Greg Burghardt
                Aug 20, 2015 at 15:04
        
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