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    <title>Serializing Dates in JSON</title>
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      <span class="productTitle">Json.NET - Quick Starts & API Documentation</span><br />
        <span class="topicTitle">Serializing Dates in JSON</span></div>

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      <span style="color: DarkGray"> </span>
        <p>DateTimes in JSON are hard.</p>
        <p>
            The problem comes from the <a href="http://www.ietf.org/rfc/rfc4627.txt" target="_blank">JSON spec</a> itself, there is no literal syntax for dates in JSON. The spec has objects, arrays, strings, integers and floats, but it defines no standard for what a date looks like.</p>
<p>The default format used by <a href="http://james.newtonking.com/projects/json-net.aspx" target="_blank">Json.NET</a> 
  is the ISO 8601 standard: 2012-03-19T07:22Z. You can read more about it <a href="http://en.wikipedia.org/wiki/ISO_8601" target="_blank">here</a>.</p>
      <p>Prior to Json.NET 4.5 dates were written using the Microsoft format: 
        &quot;\/Date(1198908717056)\/&quot;. If you want to use this format, or you want to 
        maintain compatibility with Microsoft JSON serializers or older versions of 
        Json.NET then change the DateFormatHandling setting to MicrosoftDateFormat.</p>

<h3>DateTime JsonConverters</h3>
<p>With no standard for dates in JSON, the number of possible different formats when interoping with other systems is endless. Fortunately Json.NET has a solution to deal with reading and writing custom dates: JsonConverters. A JsonConverter is used to override how a type is serialized.</p>

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<pre style="margin: 0px;"><span style="color: blue;">public</span> <span style="color: blue;">class</span> <span style="color: rgb(43, 145, 175);">LogEntry</span></pre>
<pre style="margin: 0px;">{</pre>
<pre style="margin: 0px;">&nbsp; <span style="color: blue;">public</span> <span style="color: blue;">string</span> Details { <span style="color: blue;">get</span>; <span style="color: blue;">set</span>; }</pre>

<pre style="margin: 0px;">&nbsp; <span style="color: blue;">public</span> <span style="color: rgb(43, 145, 175);">DateTime</span> LogDate { <span style="color: blue;">get</span>; <span style="color: blue;">set</span>; }</pre>
<pre style="margin: 0px;">}</pre>
<pre style="margin: 0px;">&nbsp;</pre>
<pre style="margin: 0px;">[<span style="color: rgb(43, 145, 175);">Test</span>]</pre>

<pre style="margin: 0px;"><span style="color: blue;">public</span> <span style="color: blue;">void</span> WriteJsonDates()</pre>
<pre style="margin: 0px;">{</pre>
<pre style="margin: 0px;">&nbsp; <span style="color: rgb(43, 145, 175);">LogEntry</span> entry = <span style="color: blue;">new</span> <span style="color: rgb(43, 145, 175);">LogEntry</span></pre>
<pre style="margin: 0px;">&nbsp; {</pre>

<pre style="margin: 0px;">&nbsp;&nbsp;&nbsp; LogDate = <span style="color: blue;">new</span> <span style="color: rgb(43, 145, 175);">DateTime</span>(2009, 2, 15, 0, 0, 0, <span style="color: rgb(43, 145, 175);">DateTimeKind</span>.Utc),</pre>
<pre style="margin: 0px;">&nbsp;&nbsp;&nbsp; Details = <span style="color: rgb(163, 21, 21);">"Application started."</span></pre>
<pre style="margin: 0px;">&nbsp; };</pre>
<pre style="margin: 0px;">&nbsp;</pre>

<pre style="margin: 0px;">&nbsp; <span style="color: blue;">string</span> defaultJson = <span style="color: rgb(43, 145, 175);">JsonConvert</span>.SerializeObject(entry);</pre>
<pre style="margin: 0px;">&nbsp; <span style="color: green;">// {"Details":"Application started.","LogDate":"\/Date(1234656000000)\/"}</span></pre>
<pre style="margin: 0px;"></pre>
<pre style="margin: 0px;">&nbsp;</pre>
<pre style="margin: 0px;">&nbsp; <span style="color: blue;">string</span> javascriptJson = <span style="color: rgb(43, 145, 175);">JsonConvert</span>.SerializeObject(entry, <span style="color: blue;">new</span> <span style="color: rgb(43, 145, 175);">JavaScriptDateTimeConverter</span>());</pre>

<pre style="margin: 0px;">&nbsp; <span style="color: green;">// {"Details":"Application started.","LogDate":new Date(1234656000000)}</span></pre>
<pre style="margin: 0px;">&nbsp;</pre>
<pre style="margin: 0px;">&nbsp; <span style="color: blue;">string</span> isoJson = <span style="color: rgb(43, 145, 175);">JsonConvert</span>.SerializeObject(entry, <span style="color: blue;">new</span> <span style="color: rgb(43, 145, 175);">IsoDateTimeConverter</span>());</pre>
<pre style="margin: 0px;">&nbsp; <span style="color: green;">// {"Details":"Application started.","LogDate":"2009-02-15T00:00:00Z"}</span></pre>

<pre style="margin: 0px;">}</pre>
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<p>Simply pass the JsonConverter you wish to use to the Json.NET serializer.</p>
<h4>JavaScriptDateTimeConverter</h4>
<p>The JavaScriptDateTimeConverter class is one of the two DateTime JsonConverters that come with Json.NET. This converter serializes a DateTime as a <a href="https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Global_Objects/Date" target="_blank">JavaScript Date object</a>.</p>
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<pre style="margin: 0px;">new Date(1234656000000)</pre>

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<p>Technically this is invalid JSON according to the spec but all browsers, and some JSON frameworks including Json.NET, support it. </p>
<h4>IsoDateTimeConverter</h4>
<p>IsoDateTimeConverter seralizes a DateTime to an <a href="http://en.wikipedia.org/wiki/ISO_8601" target="_blank">ISO 8601</a> formatted string. 
  Note that since Json.NET 4.5 dates are written using the ISO 8601 format by 
  default and using this converter is unnecessary.</p>
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<pre style="margin: 0px;"><span style="color: rgb(163, 21, 21);">"2009-02-15T00:00:00Z"</span></pre>

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<p>The IsoDateTimeConverter class has a property, DateTimeFormat, to further customize the formatted string.</p>
<p>&nbsp;</p>
<p>One final thing to note is all date values returned by Json.NET are in <a href="http://en.wikipedia.org/wiki/Utc" target="_blank">UTC time</a>.</p>


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