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   4     <title>Reading and Writing JSON</title>
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  12       <span class="productTitle">Json.NET - Quick Starts & API Documentation</span><br />
  13         <span class="topicTitle">Reading and Writing JSON</span></div>
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  18         <p>To manually read and write JSON Json.NET provides the <a href="./html/T_Newtonsoft_Json_JsonReader.htm">JsonReader</a> and <a href="./html/T_Newtonsoft_Json_JsonWriter.htm">JsonWriter</a> classes.</p>
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  20 <h3>JsonTextReader and JsonTextWriter</h3>
  21 <p><a href="./html/T_Newtonsoft_Json_JsonTextReader.htm">JsonTextReader</a> and <a href="./html/T_Newtonsoft_Json_JsonTextWriter.htm">JsonTextWriter</a> are used to read and write JSON text. The JsonTextWriter has a number of settings on it to control how JSON is formatted when it is written. These options include formatting, indention character, indent count and quote character.</p>
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  26 <pre style="margin: 0px;"><span style="color: #2b91af;">StringBuilder</span> sb = <span style="color: blue;">new</span> <span style="color: #2b91af;">StringBuilder</span>();</pre>
  27 <pre style="margin: 0px;"><span style="color: #2b91af;">StringWriter</span> sw = <span style="color: blue;">new</span> <span style="color: #2b91af;">StringWriter</span>(sb);</pre>
  28 <pre style="margin: 0px;">&nbsp;</pre>
  29 <pre style="margin: 0px;"><span style="color: blue;">using</span> (<span style="color: #2b91af;">JsonWriter</span> jsonWriter = <span style="color: blue;">new</span> <span style="color: #2b91af;">JsonTextWriter</span>(sw))</pre>
  30 <pre style="margin: 0px;">{</pre>
  31 <pre style="margin: 0px;">&nbsp; jsonWriter.Formatting = <span style="color: #2b91af;">Formatting</span>.Indented;</pre>
  32 <pre style="margin: 0px;">&nbsp;</pre>
  33 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteStartObject();</pre>
  34 <pre style="margin: 0px;">&nbsp; jsonWriter.WritePropertyName(<span style="color: #a31515;">"CPU"</span>);</pre>
  35 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteValue(<span style="color: #a31515;">"Intel"</span>);</pre>
  36 <pre style="margin: 0px;">&nbsp; jsonWriter.WritePropertyName(<span style="color: #a31515;">"PSU"</span>);</pre>
  37 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteValue(<span style="color: #a31515;">"500W"</span>);</pre>
  38 <pre style="margin: 0px;">&nbsp; jsonWriter.WritePropertyName(<span style="color: #a31515;">"Drives"</span>);</pre>
  39 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteStartArray();</pre>
  40 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteValue(<span style="color: #a31515;">"DVD read/writer"</span>);</pre>
  41 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteComment(<span style="color: #a31515;">"(broken)"</span>);</pre>
  42 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteValue(<span style="color: #a31515;">"500 gigabyte hard drive"</span>);</pre>
  43 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteValue(<span style="color: #a31515;">"200 gigabype hard drive"</span>);</pre>
  44 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteEnd();</pre>
  45 <pre style="margin: 0px;">&nbsp; jsonWriter.WriteEndObject();</pre>
  46 <pre style="margin: 0px;">}</pre>
  47 <pre style="margin: 0px;">&nbsp;</pre>
  48 <pre style="margin: 0px;"><span style="color: green;">// {</span></pre>
  49 <pre style="margin: 0px;"><span style="color: green;">//&nbsp;  "CPU": "Intel",</span></pre>
  50 <pre style="margin: 0px;"><span style="color: green;">//&nbsp;  "PSU": "500W",</span></pre>
  51 <pre style="margin: 0px;"><span style="color: green;">//&nbsp;  "Drives": [</span></pre>
  52 <pre style="margin: 0px;"><span style="color: green;">//&nbsp; &nbsp;  "DVD read/writer"</span></pre>
  53 <pre style="margin: 0px;"><span style="color: green;">//&nbsp; &nbsp;  /*(broken)*/,</span></pre>
  54 <pre style="margin: 0px;"><span style="color: green;">//&nbsp; &nbsp;  "500 gigabyte hard drive",</span></pre>
  55 <pre style="margin: 0px;"><span style="color: green;">//&nbsp; &nbsp;  "200 gigabype hard drive"</span></pre>
  56 <pre style="margin: 0px;"><span style="color: green;">//&nbsp;  ]</span></pre>
  57 <pre style="margin: 0px;"><span style="color: green;">// }</span></pre>
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  62 <h3>JTokenReader and JTokenWriter</h3>
  63 <p><a href="./html/T_Newtonsoft_Json_Linq_JTokenReader.htm">JTokenReader</a> and <a href="./html/T_Newtonsoft_Json_Linq_JTokenWriter.htm">JTokenWriter</a> read and write LINQ to JSON objects. They are located in the <a href="./html/N_Newtonsoft_Json_Linq.htm">Newtonsoft.Json.Linq</a> namespace. These objects allow you to use LINQ to JSON objects with objects that read and write JSON such as the JsonSerializer. For example you can deserialize from a LINQ to JSON object into a regular .NET object and vice versa.</p>
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  68 <pre style="margin: 0px;"><span style="color: #2b91af;">JObject</span> o = <span style="color: blue;">new</span> <span style="color: #2b91af;">JObject</span>(</pre>
  69 <pre style="margin: 0px;">&nbsp; <span style="color: blue;">new</span> <span style="color: #2b91af;">JProperty</span>(<span style="color: #a31515;">"Name"</span>, <span style="color: #a31515;">"John Smith"</span>),</pre>
  70 <pre style="margin: 0px;">&nbsp; <span style="color: blue;">new</span> <span style="color: #2b91af;">JProperty</span>(<span style="color: #a31515;">"BirthDate"</span>, <span style="color: blue;">new</span> <span style="color: #2b91af;">DateTime</span>(1983, 3, 20))</pre>
  71 <pre style="margin: 0px;">&nbsp; );</pre>
  72 <pre style="margin: 0px;">&nbsp;</pre>
  73 <pre style="margin: 0px;"><span style="color: #2b91af;">JsonSerializer</span> serializer = <span style="color: blue;">new</span> <span style="color: #2b91af;">JsonSerializer</span>();</pre>
  74 <pre style="margin: 0px;"><span style="color: #2b91af;">Person</span> p = (<span style="color: #2b91af;">Person</span>)serializer.Deserialize(<span style="color: blue;">new</span> <span style="color: #2b91af;">JTokenReader</span>(o), <span style="color: blue;">typeof</span>(<span style="color: #2b91af;">Person</span>));</pre>
  75 <pre style="margin: 0px;">&nbsp;</pre>
  76 <pre style="margin: 0px;"><span style="color: #2b91af;">Console</span>.WriteLine(p.Name);</pre>
  77 <pre style="margin: 0px;"><span style="color: green;">// John Smith</span></pre>
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