Parsing JSON in. Net: datacontractjsonserializer class

JSON is a lightweight text transmission format, which is generally used for front-end and back-end data exchange.

Datacontractjsonserializer is a specialized class of fm3.5 for JSON serialization and deserialization. The following is a simple application of datacontractjsonserializer.

 

Assume that the client has a JSON object, which is uploaded to the background through Ajax and parsed in the background.

 

The Code is as follows:

VaR people = [{"username": "T1", "password": "111111", "sex": "male" },{ "username": "T2 ", "password": "222222", "sex": "female"}]; <br/> var url = "default. aspx? People = "+ escape (people. tojsonstring (); <br/> request. open ("Post", URL, true); <br/> request. onreadystatechange = updatepage; <br/> request. send (null); <br/>

If the tojsonstring function runs normally, JSON. JS is referenced.

<SCRIPT src = "JSON. js" type = "text/JavaScript"> </SCRIPT>

 

Background code:

Create a test class testobj (the properties in testobj are consistent with those passed by the client)

[Datacontract] // serialization <br/> public class testobj <br/> {<br/> [datamember] <br/> Public String username {Get; set ;} <br/> [datamember] <br/> Public String password {Get; Set ;}< br/> [datamember] <br/> Public String sex {Get; set ;} </P> <p> Public testobj (string U, string P, string s) <br/>{< br/> username = u; <br/> Password = P; <br/> sex = s; <br/>}< br/>

New serialization and deserialization Methods

// JSON serialization </P> <p> Public static string tojsjson (Object item) <br/>{< br/> datacontractjsonserializer serializer = new datacontractjsonserializer (item. getType (); <br/> using (memorystream MS = new memorystream () <br/>{< br/> serializer. writeobject (MS, item); <br/> stringbuilder sb = new stringbuilder (); <br/> Sb. append (encoding. utf8.getstring (Ms. toarray (); <br/> return sb. tostring (); <br/>}</P> <p> // deserialization </P> <p> Public static t fromjsonto <t> (string jsonstring) <br/>{< br/> datacontractjsonserializer SER = new datacontractjsonserializer (typeof (t); <br/> using (memorystream MS = new memorystream (encoding. utf8.getbytes (jsonstring) <br/>{< br/> T jsonobject = (t) Ser. readobject (MS); <br/> return jsonobject; <br/>}< br/>}

 

Call:

Deserialization JSON (resolution) Note: people is passed by the client.

// Obtain the JSON string <br/> string jsonstr = request ["people"]; <br/> List <testobj> OBJ = JSON. fromjsonto <list <testobj> (jsonstr); <br/> foreach (testobj item in OBJ) <br/>{< br/> response. write (string. format ("username: {0}, password: {1}, sex: {2}/R/N", item. username, item. password, item. sex); <br/>}< br/> response. end ();

 

Serialized into a JSON string

List <testobj> Users = new list <testobj> (); <br/> users. add (New testobj ("T1", "1", "male"); <br/> users. add (New testobj ("T2", "2", "female"); <br/> string JSON = JSON. tojsjson (users); <br/> response. write (JSON); <br/> response. end ();

 

The foreground retrieves the JSON string returned by the background:

 Function updatepage () {<br/> If (request. readystate = 4) {<br/> If (request. status = 200) {<br/> var response = request. responsetext; <br/> // convert to object <br/> // method 1 <br/> response = response. parsejson (); <br/> // method 2 <br/> // response = eval ("+ response + ")"); <br/> // object access method <br/> document. getelementbyid ("d1 "). innerhtml = response [1]. sex; <br/> // directly output <br/> // document. getelementbyid ("d1 "). innerhtml = response; <br/>}< br/>