Question

Possible Duplicate:
Pick random property from a Javascript object

suppose I have a javascript object:

Config.UI.Area = {
        "uuid": {
            "_type": "string"
        },
        "frame": {
            "_type": "rect"
        },
        "zIndex": {
            "_type": "string"
        }
 }

then I want get each of the property’s name,like “uuid”,”frame”,”zIndex”
by using for loop:

var prop=config.ui.area;
var arr=new Array()
for(var i in prop){
    //do something with prop[i]?
    //arr.push(prop[i].....)?
}

I can not directly use prop[i],it would return me an object,how can I just get it’s name?

Answer 1

This would give you an array of property names:

for(var name in prop){
    //do something with prop[name]?
    arr.push(name);
}

It would also give you the names of ‘native’ properties of the Object object. To avoid that, use the hasOwnProperty method:

for(var name in prop){
    if (prop.hasOwnPropery(name) {
     arr.push(name);
    }
}