string to json and check json key -value

Question

{"loggedin":0,"error_message":"login_failed","success_message":"","username":"","sessionId":""}

this my json in string format, i have to check in javascript that loggedin value 0 or 1

Answer 1

Do you mean:

var json = {"loggedin":0,"error_message":"login_failed","success_message":"","username":"","sessionId":""}

if(json.loggedin == 0) {
   // do something
}
else {
   // do something else
}

Update:

If you have the JSON as string, you have to parse it before you can do this. So maybe you have to do this:

var responseText = JSON.parse(responseText);

Answer 2

var myJSONObject = {"loggedin":0,"error_message":"login_failed","success_message":"","username":"","sessionId":""};
if (myJSONObject.loggedin === 0) {
   // do something
} else {
   // do something else
}

Answer 3

ha ha got it, should use like this var obj = $.evalJSON(responseText); alert(obj.error_message); //output:login_failed