Check if key exists in JSON object using jQuery

I have done AJAX validation and validated message is returned as a JSON array. Therefore I need to check whether the keys, like name and email, are in that JSON array.

{
    "name": {
        "isEmpty": "Value is required and can't be empty"
    },
    "email": {
        "isEmpty": "Value is required and can't be empty"
    }
}

Only if the key name is present, I need to write an error message to the name field.

Following is the code to display an error if fields is entered

if (obj['name']'isEmpty'] != "") {                                 
   $('#name').after(c1 + "<label class='error'>" + obj['name']['isEmpty'] + "</label>");
}                                       
if (obj['email']['isEmpty'] != "" ) { 
   $('#email').after(c4 + "<label class='error'>" + obj['email']['isEmpty'] + "</label>");
}

But if the name field is entered, it will not be in JSON array. So the checking statement

if (obj['name']['isEmpty'] != "")

will result in the following error:

obj.name not found

It is not necessary to have key name in the array. At same time I need to check for this to display the error if the array possesses the key name.

Use JavaScript's hasOwnProperty() function:

if (json_object.hasOwnProperty('name')) {
    //do struff
}

No need of JQuery simply you can do

if(yourObject['email']){
 // what if this property exists.
}

as with any value for email will return you true, if there is no such property or that property value is null or undefined will result to false

if(typeof theObject['key'] != 'undefined'){
     //key exists, do stuff
}

//or

if(typeof theObject.key != 'undefined'){
    //object exists, do stuff
}

I'm writing here because no one seems to give the right answer..

I know it's old...

Somebody might question the same thing..

if you have an array

var subcategories=[{name:"test",desc:"test"}];

function hasCategory(nameStr) {
        for(let i=0;i<subcategories.length;i++){
            if(subcategories[i].name===nameStr){
                return true;
            }
        }
        return false;
    }

if you have an object

var category={name:"asd",test:""};

if(category.hasOwnProperty('name')){//or category.name!==undefined
   return true;
}else{
   return false;
}