Android requests JSON data via httpclient and resolves

Create a ashx file with. NET and Response.Write the JSON format

public void ProcessRequest (HttpContext context)        {            context. Response.ContentType = "Text/plain";            StringBuilder  Jsonbuilder  = new StringBuilder ();            Jsonbuilder.append ("{\" parent\ ":");            Jsonbuilder.append ("{\" children\ ":");            Jsonbuilder.append ("[");            Jsonbuilder.append ("{\" id\ ": \" 11111\ ", \" title\ ": \" aaaaaaa\ ", \" name\ ": \" 111111111aaaaaaaaaa\ "},");            Jsonbuilder.append ("{\" id\ ": \" 22222\ ", \" title\ ": \" bbbbbbb\ ", \" name\ ": \" 222222222aaaaaaaaaa\ "},");            Jsonbuilder.append ("{\" id\ ": \" 33333\ ", \" title\ ": \" ccccccc\ ", \" name\ ": \" 33333333aaaaaaaaaa\ "}");            Jsonbuilder.append ("]}}");             Context. Response.Write (Jsonbuilder.tostring ());        }

Android Code

public class Httpclient_get_activity extends Activity {public TextView mytextview = null; @Override protected void OnCreate (Bundle savedinstancestate) {//TODO auto-generated method stub Super.oncrea      Te (savedinstancestate);           This.setcontentview (r.layout.httpget_httpclient_activity);      Button btn = (button) This.findviewbyid (R.id.button1);              Btn.setonclicklistener (New Button.onclicklistener () {@Override public void OnClick (View v) {         New Readhttpget (). Execute ("Http://190.160.10.79:7890/handler1.ashx");   }              }); } class Readhttpget extends Asynctask<object, object, object> {@Override protected object Doinback Ground (Object ... params) {//TODO auto-generated method stub HttpGet HttpRequest = new HttpGet (PA         Rams[0].tostring ());            try {HttpClient HttpClient = new Defaulthttpclient (); HttpResponse HttpResponse = Httpclient.execute(HttpRequest); if (Httpresponse.getstatusline (). Getstatuscode () = = HTTPSTATUS.SC_OK) {String strresult = Entity                Utils.tostring (Httpresponse.getentity ());            return strresult;            } else {return "request Error";            }} catch (Clientprotocolexception e) {} catch (IOException e) {         TODO auto-generated Catch block E.printstacktrace ();      } return null; } @Override protected void oncancelled (Object result) {//TODO auto-generated method stub Supe      r.oncancelled (result); } @Override protected void OnPostExecute (Object result) {//TODO auto-generated method stub su                 Per.onpostexecute (result); try {//Create a JSON object Jsonobject jsonobject = new Jsonobject (result.tostring ()). Getjsonobject (" Parent ");                       Gets the JSON array for an object Jsonarray Jsonarray = Jsonobject.getjsonarray ("Children");                       StringBuilder builder = new StringBuilder (); for (int i = 0; I<jsonarray.length (); i++) {//Create a new JSON object that is one of the object JSON in an array                               Object jsonObject2 = (jsonobject) jsonarray.opt (i); Builder.append (jsonobject2.getstring ("id"));                Get Data Builder.append (jsonobject2.getstring ("title"));            Builder.append (jsonobject2.getstring ("name"));         } mytextview.settext (Builder.tostring ());         } catch (Jsonexception e) {//TODO auto-generated catch block E.printstacktrace ();         }} @Override protected void OnPreExecute () {//TODO auto-generated method stub         Super.onpreexecute ();   Toast.maketext (Getapplicationcontext (), "Start HTTP GET request", Toast.length_long). Show ();   } @Override protected void Onprogressupdate (Object ... values) {//TODO auto-generated method stub      Super.onprogressupdate (values); }          }}

The shallow understanding of JSON in Android

Jsonobject representation {"Key": "Value"}

Jsonarray representation [{"Key": "Value"},{"key": "Value"},{"key": "Value"}],jsonarray contains multiple Jsonobject

Access via Jsonobject object, use Jsonobject.getxxx ("key") to get the corresponding value

The general parsing JSON uses these two.