Getting specific value from JSON using javascript

问题:

I am using ajax to get a small set of data back from the server which returns JSON data with the following format:

{
    "data": [
        {
            "id": "1",
            "value": "One"
        },
        {
            "id": "2",
            "value": "Two"
        },
        {
            "id": "3",
            "value": "Three"
        }
    ]
}

On the client side, this is assigned to a variable named response. I use response.data to get the contents.

The question is, is there an easier way to get the value without doing a loop? I'm kinda looking for something like this response[id==2].value which should give me "Two".

I'm open for any suggestions if this is not possible.

回答1:

You could take a functional approach and use the Array.filter method:

var matchingResults = JSON['data'].filter(function(x){ return x.id == 2; });
// procede to use matching elements...

回答2:

If you parse it into a javascript object using something like jQuery's json parse method, you could just reference the various items in the array like a normal javascript array.

Do it like this:

var dataArray = $.parseJSON(myJson).data;

var theFirstData = dataArray[0]; //get the data with id "1"

Alternately, if you don't want to use jQuery, you can use JSON.parse(jsonToParse). Here're the docs for that method.