我将此帖子重新发布,但找不到此问题的解决方案...
这是错误
org.json.JSONException:Value <!DOCTYPE of type java.lang.String cannot be converted to JSONArray
这是JSON输出:
[{"name":"Muhaimin","address":"Sylhet","bgroup":"o+"}]
这是课程代码:
entpackage com.example.blood;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONObject;
import android.os.Bundle;
import android.os.StrictMode;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.util.Log;
import android.view.Menu;
import android.widget.TextView;
import android.widget.Toast;
@SuppressLint("NewApi")
public class MainActivity extends Activity {
TextView resultView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
StrictMode.enableDefaults();
resultView=(TextView) findViewById(R.id.result);
getData();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void getData()
{
String result="";
InputStream isr=null;
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost=new HttpPost("http://10.0.2.2/blood/index.php");
httppost.setHeader("Content-Type", "application/json");
httppost.setHeader("Accept", "JSON");
HttpResponse response=httpclient.execute(httppost);
HttpEntity entity=response.getEntity();
isr=entity.getContent();
}catch(Exception e){
String err=e.toString();
resultView.setText("Could not connect to database"+err);
Log.e("error", err);
}
try{
BufferedReader reader=new BufferedReader(new InputStreamReader(isr,"iso-8859-1"),8);
StringBuilder sb=new StringBuilder();
String line=null;
while((line = reader.readLine()) != null){
sb.append(line + "\n");
}
isr.close();
result=sb.toString();
}catch(Exception e){
String err2=e.toString();
resultView.setText("Error coverting result"+err2);
Log.e("error", err2);
}
try{
String s="";
JSONArray jArray=new JSONArray(result);
for(int i=0;i<jArray.length();i++){
JSONObject json=jArray.getJSONObject(i);
s= s +
"Name :"+json.getString("name")+"\n"+
"Blood Group :"+json.getString("bgroup")+"\n" +
"Address :"+json.getString("address")+"\n\n";
}
resultView.setText(s);
}catch(Exception e){
String err1=e.toString();
resultView.setText("xxx"+err1);
Log.e("error", err1);
}
}
}
这是PHP代码:
<?php
$con=mysql_connect("localhost","root","","BloodDB");
mysql_select_db("BloodDB",$con);
$result=mysql_query("SELECT name,address,bgroup FROM tbl_blood_donor");
while($row=mysql_fetch_assoc($result))
{
$output[]=$row;
}
print(json_encode($output));
mysql_close($con);
?>
现在如何解决这个问题。我提前在localhost.thanks工作
最佳答案
您的问题不在JSON中,也不在JSONArray中,因此,如果遇到此异常,则意味着JSONArray的字符串与您预期的不同。
在此行“ JSONArray jArray = new JSONArray(result);”之前打印字符串结果和字符串长度。您可以使用以下打印消息
Log.d(“ My String”,“ string result:[” + result +“],其长度为:” + result.length());
请注意,我使用了下面的代码,它工作正常
String str = "[{\"name\":\"Muhaimin\",\"address\":\"Sylhet\",\"bgroup\":\"o+\"}]";
try {
JSONArray json = new JSONArray(str);
Log.d(TAG, "Json value :" + json);
Log.d(TAG, "Json value :" + json.getJSONObject(0).getString("bgroup"));
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
结果:
Json值:[{“ bgroup”:“ o +”,“地址”:“ Sylhet”,“名称”:“ Muhaimin”}]
Json值:o +