分析Json字符串时出错无法转换为对象

Question

我做了一个http://androidhive.com项目，名为android登录和resgitration..when我运行我的项目时更新我的​​本地服务器..但该应用程序在logcat中崩溃并出现以下错误

..03-04 09:40:47.284: E/JSON(22069): nnnnnInside config{"tag":"register","success":1,"error":0,"uid":"51346c28f08575.36974266","user":{"name":"sdfds","email":"[email protected]","created_at":"2013-03-04 01:40:56","updated_at":null}}n 
03-04 09:40:47.306: E/JSON Parser(22069): Error parsing data org.json.JSONException: Value nnnnnInside of type java.lang.String cannot be converted to JSONObject 
03-04 09:40:47.387: E/AndroidRuntime(22069): FATAL EXCEPTION: main 
03-04 09:40:47.387: E/AndroidRuntime(22069): java.lang.NullPointerException 
03-04 09:40:47.387: E/AndroidRuntime(22069): at com.androidhive.httprequests.RegisterActivity$1.onClick(RegisterActivity.java:60) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at android.view.View.performClick(View.java:4202) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at android.view.View$PerformClick.run(View.java:17340) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at android.os.Handler.handleCallback(Handler.java:725) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at android.os.Handler.dispatchMessage(Handler.java:92) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at android.os.Looper.loop(Looper.java:137) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at android.app.ActivityThread.main(ActivityThread.java:5039) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at java.lang.reflect.Method.invokeNative(Native Method) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at java.lang.reflect.Method.invoke(Method.java:511) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 
03-04 09:40:47.387: E/AndroidRuntime(22069): at dalvik.system.NativeStart.main(Native Method) 

和我的JSON代码

enter code herepackage com.example.androidhive.library; 
import java.io.BufferedReader; 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.InputStreamReader; 
import java.io.UnsupportedEncodingException; 
import java.util.List; 
import org.apache.http.HttpEntity; 
import org.apache.http.HttpResponse; 
import org.apache.http.NameValuePair; 
import org.apache.http.client.ClientProtocolException; 
import org.apache.http.client.entity.UrlEncodedFormEntity; 
import org.apache.http.client.methods.HttpPost; 
import org.apache.http.impl.client.DefaultHttpClient; 
import org.apache.http.protocol.HTTP; 
import org.json.JSONException; 
import org.json.JSONObject; 

import android.content.Context; 
import android.util.Log; 
import android.widget.Toast; 

public class JSONParser { 
    Context context; 
    static InputStream is = null; 
    static JSONObject jObj = null; 
    static String json = ""; 

    // constructor 
    public JSONParser() { 

    } 

    public JSONObject getJSONFromUrl(String url, List<NameValuePair> params) { 

     // Making HTTP request 
     try { 
      // defaultHttpClient 
      DefaultHttpClient httpClient = new DefaultHttpClient(); 
      HttpPost httpPost = new HttpPost(url); 
      httpPost.setEntity(new UrlEncodedFormEntity(params,HTTP.UTF_8)); 

      HttpResponse httpResponse = httpClient.execute(httpPost); 
      HttpEntity httpEntity = httpResponse.getEntity(); 
      is = httpEntity.getContent(); 

     } catch (UnsupportedEncodingException e) { 
      e.printStackTrace(); 
     } catch (ClientProtocolException e) { 
      e.printStackTrace(); 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 

     try { 
      BufferedReader reader = new BufferedReader(new InputStreamReader(
        is, "UTF-8"), 8); 
      StringBuilder sb = new StringBuilder(); 
      String line = null; 
      while ((line = reader.readLine()) != null) { 
       sb.append(line + "n"); 
      } 
      is.close(); 
      json = sb.toString(); 
      Log.e("JSON", json); 
     } catch (Exception e) { 
      Log.e("Buffer Error", "Error converting result " + e.toString()); 
     } 

     // try parse the string to a JSON object 
     try { 
      jObj = new JSONObject(json); 
     } catch (JSONException e) { 
      Log.e("JSON Parser", "Error parsing data " + e.toString()); 
     } 

     // return JSON String 
     return jObj; 

    }`enter code here` 
} 

我阅读栈溢出所有的答案可能让新台币帮anything..pls我在此先感谢

package com.androidhive.httprequests; 

import org.json.JSONException; 
import org.json.JSONObject; 

import android.app.Activity; 
import android.content.Intent; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.TextView; 
import android.widget.Toast; 

import com.example.androidhive.library.DatabaseHandler; 
import com.example.androidhive.library.UserFunctions; 
import com.example.androidhive.library.JSONParser; 
public class RegisterActivity extends Activity { 
    Button btnRegister; 
    Button btnLinkToLogin; 
    EditText inputFullName; 
    EditText inputEmail; 
    EditText inputPassword; 
    TextView registerErrorMsg; 

    // JSON Response node names 
    private static String KEY_SUCCESS = "success"; 
    private static String KEY_ERROR = "error"; 
    private static String KEY_ERROR_MSG = "error_msg"; 
    private static String KEY_UID = "uid"; 
    private static String KEY_NAME = "name"; 
    private static String KEY_EMAIL = "email"; 
    private static String KEY_CREATED_AT = "created_at"; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.register); 

     // Importing all assets like buttons, text fields 
     inputFullName = (EditText) findViewById(R.id.registerName); 
     inputEmail = (EditText) findViewById(R.id.registerEmail); 
     inputPassword = (EditText) findViewById(R.id.registerPassword); 
     btnRegister = (Button) findViewById(R.id.btnRegister); 
     btnLinkToLogin = (Button) findViewById(R.id.btnLinkToLoginScreen); 
     registerErrorMsg = (TextView) findViewById(R.id.register_error); 

     // Register Button Click event 
     btnRegister.setOnClickListener(new View.OnClickListener() { 
      public void onClick(View view) { 
       //Toast.makeText(getBaseContext(), "Inside btnregister", Toast.LENGTH_SHORT).show(); 
       String name = inputFullName.getText().toString(); 
       String email = inputEmail.getText().toString(); 
       String password = inputPassword.getText().toString(); 
       UserFunctions userFunction = new UserFunctions(); 
       JSONObject json = userFunction.registerUser(name, email, password); 

       // check for login response 
       try { 
        if (json.getString(KEY_SUCCESS) != null) { 
         registerErrorMsg.setText(""); 
         String res = json.getString(KEY_SUCCESS); 
         if(Integer.parseInt(res) == 1){ 
          // user successfully registred 
          // Store user details in SQLite Database 
          DatabaseHandler db = new DatabaseHandler(getApplicationContext()); 
          JSONObject json_user = json.getJSONObject("user"); 

          // Clear all previous data in database 
          userFunction.logoutUser(getApplicationContext()); 
          db.addUser(json_user.getString(KEY_NAME), json_user.getString(KEY_EMAIL), json.getString(KEY_UID), json_user.getString(KEY_CREATED_AT)); 
          // Launch Dashboard Screen 
          Intent dashboard = new Intent(getApplicationContext(), DashboardActivity.class); 
          // Close all views before launching Dashboard 
          dashboard.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
          startActivity(dashboard); 
          // Close Registration Screen 
          finish(); 
         }else{ 
          // Error in registration 
          registerErrorMsg.setText("Error occured in registration"); 
         } 
        } 
       } catch (JSONException e) { 
        e.printStackTrace(); 
       } 
      } 
     }); 

     // Link to Login Screen 
     btnLinkToLogin.setOnClickListener(new View.OnClickListener() { 

      public void onClick(View view) { 
       Intent i = new Intent(getApplicationContext(), 
         Login.class); 
       startActivity(i); 
       // Close Registration View 
       finish(); 
      } 
     }); 
    } 
} 

这里是我的注册活动

Answer 1

因为你JSON字符串不是转化为JsonObject有效。你将需要使用字符串函数首先使它成为一个有效的JSON字符串，然后将其转换为JSONObject的为：

// your code here.. 
is.close(); 
json = sb.toString(); 
String str_json = json.replace("nnnnnInside config{", ""); 
String final_json=str_json.replace("}}n", "}}"); 
Log.e("JSON", json); 

/// now convert final_json to json object 
jObj = new JSONObject(final_json);