Need to convert json key-value pairs to standard array

Question

I'm interperting a json string into a variable using jquery's parseJSON() function. The problem is, it's turning my data into an object instead of a 2d array. Eg,

myData = $.parse(JSON(data));
myData.name// = "Bob"

The problem is, "name" is not supposed to be a key (assuming that is the correct term). Instead, it should be:

myData[0] // = "name"
myData[1] // = "Bob"

How would I convert this? Or is there a different method than using a for loop to walk through the index of an array (but still be able to access both key and value as a string, as you would in a 2d array).

EDIT: This is some json that is in use (Note it's MUCH longer). This is what is given for "data"

{"feat_3":"4356","feat_4":"45","feat_5":"564","feat_6":"7566"}

It seems a bit of an odd thing to do, if you don't mind my saying. Why create a flat array with both the keys and their values? — T.J. Crowder, Jan 09 '12 at 08:46
where is bob then? because it would be like feat_3 could be bob instead of 4356 — Teun Pronk, Jan 09 '12 at 08:49
Yeah, I used your example rather than moving it to a "flat array" which makes much more sense. — Radley Sustaire, Jan 09 '12 at 08:50
@Teun, in that example bob it would have been {"name":"Bob"} — Radley Sustaire, Jan 09 '12 at 08:50

score 5 · Accepted Answer · answered Jan 09 '12 at 08:42

Once you've deserialized the data (e.g., you have myData, which is an object), you can loop through its keys using for..in, and then build up an array that combines keys and values:

var myData, dataArray, key;
myData = $.parse(JSON(data));
dataArray = [];
for (key in myData) {
    dataArray.push(key);         // Push the key on the array
    dataArray.push(myData[key]); // Push the key's value on the array
}

Since myData is the result of deserializing the JSON in data, we know that myData is a generic object (e.g., just a {} as opposed to a new Foo or something like that), so we don't even need hasOwnProperty. If we didn't know that, and we only wanted to enumerate myData's own keys and values, we would add a hasOwnProperty check:

var myData, dataArray, key;
myData = $.parse(JSON(data));
dataArray = [];
for (key in myData) {
    if (myData.hasOwnProperty(key)) {
        dataArray.push(key);         // Push the key on the array
        dataArray.push(myData[key]); // Push the key's value on the array
    }
}

There's no reason to do that in your case, unless someone has been mucking about with Object.prototype (in which case, take them behind the woodshed, give them a severe hiding, and then have them write "I will not muck about with Object.prototype several hundred times on the chalkboard), but whenever you use for..in, it's always good to stop and think whether A) The object is guaranteed to be vanilla, and B) If not, do you want only its own properties, or do you also want ones it inherits?

The first code block worked golden. The way it works out, I don't even need to move them to a new array. I can just assign the data in that loop itself. Wonderful! Thanks — Radley Sustaire, Jan 09 '12 at 08:49

abuduba · Answer 2 · 2012-01-09T08:53:26.940

1

var data = $.parse(JSON({"feat_3":"4356","feat_4":"45","feat_5":"564","feat_6":"7566"}));

var arr = [];

for( var i in data ) { 
  if( data.hasOwnProperty( i ) ){ 
    arr.push( i,  data[i] );
  }
}

Array will be :

["feat_3", "4356", "feat_4", "45", "feat_5", "564", "feat_6", "7566"]

edited Jan 09 '12 at 08:53

answered Jan 09 '12 at 08:43

abuduba

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Thanks, but I found TJ's solution to be a better solution than converting to 2d arrays like I had originally planned. – Radley Sustaire Jan 09 '12 at 08:52
Corrected. Into `push` method you can apply more than one argument which will filled out an array – abuduba Jan 09 '12 at 08:56

Need to convert json key-value pairs to standard array

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