iterate through json and access two dimensions deep

I'm returning rows from a mysql database in php and then making an array of all these rows and then json encoding this. I am then trying to turn that json into autocomplete for jquery, not that relavent. The issue I have is that once I have it in json, there is no defining the rows. How do I access the same json.id that is in every "r开发者_StackOverflow中文版ow" returned in json? here is a sample json object I'm using

      [{"id":"95833","fname":"john","lname":"walker","email":"john.walker@john.edu","major":"UNDECID  ED","year":"14","gender":"0","created":"0000-00-00 00:00:00"},        {"id":"95834","fname":"joseph","lname":"train","email":"jo.train@john.edu","major":"","year":"  12","gender":"0","created":"0000-00-00 00:00:00"}]

I do I access the first id, or the second one?, etc

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Here's some sample code showing how to iterate over your data:

var data = [{"id":"95833","fname":"john","lname":"walker","email":"john.walker@john.edu","major":"UNDECID  ED","year":"14","gender":"0","created":"0000-00-00 00:00:00"},        {"id":"95834","fname":"joseph","lname":"train","email":"jo.train@john.edu","major":"","year":"  12","gender":"0","created":"0000-00-00 00:00:00"}];
for( var i = 0; i < data.length; i ++ )
{
    var item = data[i];
    var thisID = item.id;
    // do something clever here
}

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jQuery will parse the JSON into a Javascript array of objects for you:

data[0].id // First id
data[1].id // Second id

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I think, I think you're trying to access the "columns", not the rows. Incidentally, this general problem of the relation model of the a SQL database not matching the object model of most languages is called "The Impedance Mismatch", and it sucks. Your particular issue could be addressed (in jQuery) with:

$.map(data, function(n) { return n.id } );

Which will return an array containing all the id values.

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If you are using jQuery 1.6 then it's very simple

// to get ['id', 'fname', 'lname', 'email', 'major', 'year', 'gender', 'created']
// you only need to map the first element of the data array and return the key.

var columnArray = $.map(data[0], function (val, k) {
    return k;
});

Happy Coding :)