C # parse Json data

JSON (fully called JavaScript Object Notation) is a lightweight data exchange format. It is a subset based on JavaScript syntax standards. JSON is in a language-independent text format and can be easily transmitted between various networks, platforms, and programs. The JSON syntax is simple, easy for reading and writing, and easy for machine parsing and generation.

Comparison between JSON and XML
◆ Readability
Compared to the readability of JSON and XML, XML provides auxiliary labels, which are more suitable for reading and understanding.
◆ File size and transmission
XML allows easy-to-use labels, so the file size is larger than JSON. JSON is derived from Javascript, so Javascript and the network are the natural battlefield. Here, JSON has the advantage that XML cannot catch up.

JSON syntax
1. JSON syntax is a subset of the syntax of JavaScript Object Notation.

• Data in name/value pairs: The name is a string, expressed in double quotation marks. The value can be a number (integer or floating point number), a string (in double quotation marks), an array (in square brackets), an object (in curly brackets), true/false/null.
• Data are separated by commas:
• Brackets save objects: objects can contain various types of data, including arrays.
• Square brackets save an array: numbers can contain objects.

For example:

2. If JSON contains escape characters, escape is required. For example, you must use "\" instead of "\" in the file path "\". For example: {"file": "C: \ a.txt "}.

 

. Net json operation
The JSON file is read into the memory as a string, and The. NET Operation JSON is to generate and parse the JSON string. JSON operations can be performed in the following ways:
1. Original Method: Write code to directly operate the JSON string according to the JSON syntax format. Unless necessary, few people should follow this path and start from scratch.

2. General method 【★★★★★]:

This approach is to use the open source class library Newtonsoft. Json (http://json.codeplex.com /). After the download, add the project to use it. Generally, JObject, JsonReader, and JsonWriter can be used for processing. This method is the most common and flexible, and can be modified at any time.
(1) Use JsonReader to read Json strings:

 jsonText = =  JsonTextReader(+  + reader.ValueType +  +

StringWriter sw = =  jsonText =

JObject jo =[] values = jo.Properties().Select(item => item.Value.ToString()).ToArray();

Array data

 jsonArrayText1 = = ja1a = ja[][JObject o = (JObject)ja[ oa = o[].ToString();

Nested format

 jsonText = = zone = jo[][ zone_en = jo[][].ToString();

Custom Project

Project p =  Project() { Input = , Output = = = =  StringReader(= (Project)serializer.Deserialize( JsonTextReader(sr), +  + p1.Output);

The above code is defined based on the following Project class:

  Input { ;   Output { ; 

In addition, if the above JsonTextReader and other classes cannot be compiled, it indicates that it is the class we have modified. you can replace it with your own related classes without affecting usage.

3. built-in Methods: Use the JavaScriptSerializer class in the System. Web. Script. Serialization namespace provided in. NET Framework 3.5/4.0 to serialize and deserialize objects directly.

Project p =  Project() { Input = , Output = =  json = p1 = serializer.Deserialize<Project>+  +

Note:If VS2010 is used, the Target Framework of the current project must be changed to. Net Framework 4, and the Client Profile cannot be used. Of course, this System. Web. Extensions. dll is mainly used by the Web, and it feels a waste of resources to be used directly in the Console project.
In addition, you can see from the last sentence,Serialization and deserialization are typical implementations of deep copy..

4. Contract Mode: Use the DataContractJsonSerializer or JsonReaderWriterFactory provided by System. Runtime. Serialization. dll.

Project p =  Project() { Input = , Output = =  (MemoryStream stream = = (MemoryStream ms = =  DataContractJsonSerializer(=+  +

Note that the Project class and members must add the relevant Attribute:

  Input { ;   Output { ; 

Practical reference:

JSON concise Tutorial: http://www.w3school.com.cn/json/
Newtonsoft. Json class library download: http://json.codeplex.com/

Reprinted from: http://www.cnblogs.com/txw1958/archive/2012/08/01/csharp-json.html

C # How to parse data in json format