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How to use JSON.parse reviver parameter to parse date string

Answer 1

+1 A:

The regular expression expects a "Zulu" timezone (A 'Z' character at the end), while the sample date-time string shows a numeric timezone ('-04:00'). The following regex will accept both:
```
/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2}(?:\.\d*)?)(Z|([+\-])(\d{2}):(\d{2}))$/
```
If the time zone digits are not zero, you might want to actually modify the date after parsing and/or converting to UTC, to respect the timezone.

I can see dateReviver() being hit. Try the following in a browser:

<!-- saved from url=(0014)about:internet -->
<html>
    <head>
        <script src="http://www.json.org/json2.js"&gt;&lt;/script&gt;
        <script type="text/javascript" src="http://ajax.Microsoft.com/ajax/jQuery/jquery-1.3.2.js"&gt;&lt;/script&gt;
        <script>
            $(function () {
                // a mock proxy to return some json to play with
                var proxy = {
                    getArticle: function(id, foo) { foo({
                        result: '["2009-04-04T22:55:16.0000000-04:00"]'
                    }); }
                };
                // the origial Site object, with the fixed regex
                var Site = {
                    dateReviver: function(key, value) {
                        var a;
                        if (typeof value === 'string') {
                            a = /^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2}(?:\.\d*)?)(Z|([+\-])(\d{2}):(\d{2}))$/.exec(value);
                            if (a) {
                                return new Date(Date.UTC(+a[1], +a[2] - 1, +a[3], +a[4],
                                                +a[5], +a[6]));
                            }
                        }
                        return value;
                    },
                    loadArticle: function(id) {
                        proxy.getArticle(id, function(response) {
                            var data = JSON.parse(response.result, Site.dateReviver);
                            // put the parsed JSON date on the page
                            $("#output").html(data[0].toString());
                        });
                    }
                };
                // try out our Site object
                Site.loadArticle();
            });
        </script>
    </head>
    <body>
        <div id="output"></div>
    </body>
</html>

I am getting the following in the browser, indicating successful parsing:

Sat Apr 4 15:55:16 PDT 2009

Oren Trutner 2009-11-24 22:45:58

Thank you Oren;)Eventually I found out the problem with your help. I was using json.js file that comes with jayrock which doesn't accept reviver parameter in parse function.What I did was using eval method instead to parse(this is where it sounds weird) JSON string :sI am more than grateful;)

Aleyna 2009-11-26 02:20:27

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How to use JSON.parse reviver parameter to parse date string

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