在JSON中搜索数据-JavaScript

Question

I have a json output as

amt: "10.00"
email: "sam@gmail.com"
merchant_id: "sam"
mobileNo: "9874563210"
orderID: "123456"
passkey: "1234"

Literally Im trying to do this in javascript

if(the json output has the key merchant_id)
{
//do something
}

How is it possible to find if a json output has a key like as I demonstrated above?Is it possible,Or is there any alternate method for it?

Answer 1

Let's say you have JSON object like this:

var json = {
   amt: "10.00",
   email: "sam@gmail.com",
   merchant_id: "sam",
   mobileNo: "9874563210",
   orderID: "123456",
   passkey: "1234"
}

So now you have to use a loop. Eg

for(var j in json) { // var j is the key in this loop
   if(j == 'merchant_id') {
      // do something
   }
}

Answer 2

You can just check the type of of the field.

if (typeof json.property !== 'undefined') {
    //has property
}

Answer 3

If this is a multiline string like you wrote it, a simple way is:

if(s.indexOf("\nmerchant_id: \"whatever\"\n")>-1) {
    // ...
}

But you can parse it of course, and that's the elegant way. With a json object, you can just refer to the field with a dot, like "obj.merchant_id".

Answer 4

For example, try this:

var data = {
   amt: "10.00",
   email: "sam@gmail.com",
   merchant_id: "sam",
   mobileNo: "9874563210",
   orderID: "123456",
   passkey: "1234"
}

if(data.amt == 'something'){
   // do work
}