>我正在构建一个安卓应用程序，它将在表"产品"中搜索mysql DB。如果我输入产品名称，它将检索产品价格，增值税和序列号。但是代码给出了"jassonArrayFail"输出。我无法理解错误。请帮忙。问题出在//parse json data try{} 块中。
java代码是：
package selva.db;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.text.NumberFormat;
import java.util.ArrayList;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
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.message.BasicNameValuePair;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.os.Bundle;
import android.os.StrictMode;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class select extends Activity
{
StrictMode.ThreadPolicy policy = new
StrictMode.ThreadPolicy.Builder().permitAll().build();
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.select);
Button button = (Button) findViewById(R.id.button1);
StrictMode.setThreadPolicy(policy);
button.setOnClickListener(new View.OnClickListener()
{
public void onClick(View view)
{
String result = null;
InputStream is = null;
EditText editText = (EditText)findViewById(R.id.e1);
String v1 = editText.getText().toString();
EditText editText1 = (EditText)findViewById(R.id.e2);
EditText editText2 = (EditText)findViewById(R.id.e3);
EditText editText3 = (EditText)findViewById(R.id.e4);
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("f1",v1));
try
{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://crimereport.site88.net/select123.php");
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity = response.getEntity();
is = entity.getContent();
Log.e("log_tag", "connection success ");
// Toast.makeText(getApplicationContext(), "pass", Toast.LENGTH_SHORT).show();
}
catch(Exception e)
{
Log.e("log_tag", "Error in http connection "+e.toString());
Toast.makeText(getApplicationContext(), "Connection fail", Toast.LENGTH_SHORT).show();
}
//convert response to string
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null)
{
sb.append(line + "'n");
// Toast.makeText(getApplicationContext(), "Input Reading pass", Toast.LENGTH_SHORT).show();
}
is.close();
result=sb.toString();
}
catch(Exception e)
{
Log.e("log_tag", "Error converting result "+e.toString());
Toast.makeText(getApplicationContext(), " Input reading fail", Toast.LENGTH_SHORT).show();
}
//parse json data
try{
JSONObject object = new JSONObject(result);
String ch=object.getString("re");
if(ch.equals("success"))
{
JSONObject no = object.getJSONObject("0");
//long q=object.getLong("f1");
int w=no.getInt("price");
int e=no.getInt("vat");
int s=no.getInt("serial");
// editText1.setText(w);
String myString1 = NumberFormat.getInstance().format(w);
editText1.setText(myString1);
String myString = NumberFormat.getInstance().format(e);
editText2.setText(myString);
String myString2 = NumberFormat.getInstance().format(s);
editText3.setText(myString2);
}
else
{
Toast.makeText(getApplicationContext(), "Record is not available.. Enter valid number", Toast.LENGTH_SHORT).show();
}
}
catch(JSONException e)
{
Log.e("log_tag", "Error parsing data "+e.toString());
Toast.makeText(getApplicationContext(), "JsonArray fail", Toast.LENGTH_SHORT).show();
}
}
});
}
}
PHP代码是：
<?php
$con = mysql_connect("mysql1.000webhost.com","a4879149_crime","myprojects333");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
mysql_select_db("a4879149_info", $con);
$v1=$_REQUEST['f1'];
//$v1='111';
if($v1==NULL)
{
$r["re"]="Enter the product!!!";
print(json_encode($r));
die('Could not connect: ' . mysql_error());
}
else
{
// $v1="530";
$i=mysql_query("SELECT * FROM product WHERE '$v1'=product",$con);
$check='';
while($row = mysql_fetch_array($i))
{
$r[]=$row;
$check=$row['product'];
// print(json_encode($r));
}
if($check==NULL)
{
$r["re"]="Product is not available";
print(json_encode($r));
}
else
{
$r["re"]="success";
//print(json_encode($r));
// die('Could not connect: ' . mysql_error());
}
}
mysql_close($con);
?>
您的代码不会总是返回 json（来自 php），这意味着很有可能没有适当的 json 字符串来解析。我会将您的代码 （php） 更改为以下内容：
$response = array();
$con = mysql_connect("mysql1.000webhost.com","a4879149_crime","myprojects333");
if (!$con) {
die('Could not connect: ' . mysql_error());
}
mysql_select_db("a4879149_info", $con);
$v1 = $_REQUEST['f1'];
if (empty($v1)) {
$response["re"] = "Enter the product!!!";
} else {
$i = mysql_query("SELECT * FROM product WHERE '$v1' = product", $con);
while($row = mysql_fetch_array($i)) {
$response[] = $row;
}
if (empty($response)) {
$r["re"] = "Product is not available";
} else {
$r["re"] = "success";
}
}
mysql_close($con);
echo json_encode($response);
die;
如果成功，这应该始终返回如下响应：
{"re":"success","0":{"productId":1},"1":{"productId":2}}
或者在出现错误的情况下：
{"re":"Enter the product!!!"}