[jQuery] How to load form fields with JSON

[jQuery] How to load form fields with JSON


I'm noob in Jquery, can you show me better way how to load form with
JSON - plugin or anything else...
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I have JSON
[{"Id":5},{"Instance":"Hello there Franky"}]
and I want to load form where key of JSON object is ID attribute of
the field.
I came up with this:
<script>
function loadform(formid, url){
    $.getJSON(url, function(json){
        var forma = $('#'+formid);
        for (var i = 0; i < json.length; i++) {
            for ( key in json[i]){
                var value = eval('json[i].'+key);
                $("#"+key, forma).attr({value:value});
            }
        }
    });
}
</script>