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Get the largest value from Json object with Javascript

This should be an easy one. I just cant figure it out.

How do I get the largest value from this piece of JSON with javascript.

{"data":{"one":21,"two":35,"three":24,"four":2,"five":18},"meta":{"title":"Happy with the service"}}

The key and value I need is:

"two":35 

as it is the highest

thanks

var jsonText = '{"data":{"one":21,"two":35,"three":24,"four":2,"five":18},"meta":{"title":"Happy with the service"}}'
var data = JSON.parse(jsonText).data
var maxProp = null
var maxValue = -1
for (var prop in data) {
  if (data.hasOwnProperty(prop)) {
    var value = data[prop]
    if (value > maxValue) {
      maxProp = prop
      maxValue = value
    }
  }
}

If you have underscore :

var max_key = _.invert(data)[_.max(data)];

How this works:

var data = {one:21, two:35, three:24, four:2, five:18};
var inverted = _.invert(data); // {21:'one', 35:'two', 24:'three', 2:'four', 18:'five'};
var max = _.max(data); // 35
var max_key = inverted[max]; // {21:'one', 35:'two', 24:'three', 2:'four', 18:'five'}[35] => 'two'

This is my function for biggest key

function maxKey(a) {  
  var max, k; // don't set max=0, because keys may have values < 0  
  for (var key in a) { if (a.hasOwnProperty(key)) { max = parseInt(key); break; }} //get any key  
  for (var key in a) { if (a.hasOwnProperty(key)) { if((k = parseInt(key)) > max) max = k; }}  
  return max;  
} 

You can also iterate the object after you parse JSON .

var arr = jQuery.parseJSON('{"one":21,"two":35,"three":24,"four":2,"five":18}' );

var maxValue = 0;

for (key in arr)
{
     if (arr[key] > maxValue)
     {
          maxValue = arr[key];   
     }
}

console.log(maxValue);

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