Getting JavaScript object key list

Question

I have a JavaScript object like

var obj = {
   key1: \'value1\',
   key2: \'value2\',
   key3: \'value3\',
   key4: \'value4\'
}

How can I

Answer 1

var keys = new Array();
for(var key in obj)
{
   keys[keys.length] = key;
}

var keyLength = keys.length;

to access any value from the object, you can use obj[key];