Java 我在解析数据时出错 org.json.JSONException
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I am getting Error parsing data org.json.JSONException
提问by Yasir
I am getting this error in my LogCat:
我在 LogCat 中收到此错误：
Error parsing data org.json.JSONException: Value ? of type java.lang.String cannot be converted to JSONArray
Below are every file I could show you! Please let me know the problem and its solution ASAP. What I guess is: 1. Maybe the is problem is with parsing data in JSON array. 2. Maybe the problem is with my php api, I think I am not properly encoding the json_encode because it gives me RAW JSON, like every thing in one line.
以下是我可以向您展示的每个文件！请尽快让我知道问题及其解决方案。我的猜测是： 1. 也许问题在于解析 JSON 数组中的数据。2.也许问题出在我的php api上，我想我没有正确编码json_encode，因为它给了我RAW JSON，就像一行中的每一件事一样。
as below
如下
?[{"uid":"120","name":"MyFirstName MyLastName"}]
Please also let me know, their is some difference in working of both format, 1. Raw JSON and 2. Intented Json
还请让我知道，它们在两种格式的工作上有所不同，1. Raw JSON 和 2. Intented Json
below is the intented json format
以下是预期的 json 格式
?[
{
"uid":"120",
"name":"MyFirstName MyLastName"
}
]
Here is the JSONUseActivity.java
这是 JSONUseActivity.java
package com.example.oncemore;
import java.util.ArrayList;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.os.Bundle;
import android.os.StrictMode;
import com.example.oncemore.CustomHttpClient;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class JSONUseActivity extends Activity {
EditText email,password;
Button submit;
TextView tv; // TextView to show the result of MySQL query
String returnString; // to store the result of MySQL query after decoding
// JSON
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder()
.detectDiskReads().detectDiskWrites().detectNetwork() // StrictMode is
// most commonly
// used to catch
// accidental
// disk or
// network
// access on the
// application's
// main thread
.penaltyLog().build());
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_jsonuse);
email = (EditText) findViewById(R.id.email);
password = (EditText) findViewById(R.id.password);
submit = (Button) findViewById(R.id.submitbutton);
tv = (TextView) findViewById(R.id.showresult);
// define the action when user clicks on submit button
submit.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// declare parameters that are passed to PHP script i.e. the
ArrayList<NameValuePair> postParameters = new ArrayList<NameValuePair>();
// define the parameter
postParameters.add(new BasicNameValuePair("email",email.getText().toString()));
postParameters.add(new BasicNameValuePair("password",password.getText().toString()));
String response = null;
// call executeHttpPost method passing necessary parameters
try {
response = CustomHttpClient.executeHttpPost(
"http://mywebsite.com/android/api.php",
postParameters);
// store the result returned by PHP script that runs MySQL
// query
String result = response.toString();
// parse json data
try {
returnString = "";
//I think the line below is creating some problem
JSONArray jArray = new JSONArray(result);
for (int i = 0; i < jArray.length(); i++) {
JSONObject json_data = jArray.getJSONObject(i);
Log.i("log_tag",
"id: " + json_data.getInt("uid")+", name: " + json_data.getString("name"));
// Get an output to the screen
returnString += "\n" + json_data.getString("name")
+ " -> " + json_data.getInt("uid");
}
}catch (JSONException e) {
Log.e("log_tag", "Error parsing data " + e.toString());
}
try {
tv.setText(returnString);
}
catch (Exception e) {
Log.e("log_tag", "Error in Display!" + e.toString());
;
}
}
catch (Exception e) {
Log.e("log_tag",
"Error in http connection!!" + e.toString());
}
}
});
}
}
}
Here is the CustomHttpClient.java
这是 CustomHttpClient.java
package com.example.oncemore;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URI;
import java.util.ArrayList;
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.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.params.ConnManagerParams;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import android.util.Log;
public class CustomHttpClient {
/** The time it takes for our client to timeout */
public static final int HTTP_TIMEOUT = 30 * 1000; // milliseconds
/** Single instance of our HttpClient */
private static HttpClient mHttpClient;
/**
* Get our single instance of our HttpClient object.
*
* @return an HttpClient object with connection parameters set
*/
private static HttpClient getHttpClient() {
if (mHttpClient == null) {
mHttpClient = new DefaultHttpClient();
final HttpParams params = mHttpClient.getParams();
HttpConnectionParams.setConnectionTimeout(params, HTTP_TIMEOUT);
HttpConnectionParams.setSoTimeout(params, HTTP_TIMEOUT);
ConnManagerParams.setTimeout(params, HTTP_TIMEOUT);
}
return mHttpClient;
}
/**
* Performs an HTTP Post request to the specified url with the specified
* parameters.
*
* @param url
* The web address to post the request to
* @param postParameters
* The parameters to send via the request
* @return The result of the request
* @throws Exception
*/
public static String executeHttpPost(String url, ArrayList<NameValuePair> postParameters) throws Exception {
BufferedReader in = null;
try {
HttpClient client = getHttpClient();
HttpPost request = new HttpPost(url);
UrlEncodedFormEntity formEntity = new UrlEncodedFormEntity(postParameters);
request.setEntity(formEntity);
HttpResponse response = client.execute(request);
in = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));
StringBuffer sb = new StringBuffer("");
String line = "";
String NL = System.getProperty("line.separator");
while ((line = in.readLine()) != null) {
sb.append(line + NL);
}
in.close();
String result = sb.toString();
return result;
} finally {
if (in != null) {
try {
in.close();
} catch (IOException e) {
Log.e("log_tag", "Error converting result "+e.toString());
e.printStackTrace();
}
}
}
}
/**
* Performs an HTTP GET request to the specified url.
*
* @param url
* The web address to post the request to
* @return The result of the request
* @throws Exception
*/
public static String executeHttpGet(String url) throws Exception {
BufferedReader in = null;
try {
HttpClient client = getHttpClient();
HttpGet request = new HttpGet();
request.setURI(new URI(url));
HttpResponse response = client.execute(request);
in = new BufferedReader(new InputStreamReader(response.getEntity()
.getContent()));
StringBuffer sb = new StringBuffer("");
String line = "";
String NL = System.getProperty("line.separator");
while ((line = in.readLine()) != null) {
sb.append(line + NL);
}
in.close();
String result = sb.toString();
return result;
} finally {
if (in != null) {
try {
in.close();
} catch (IOException e) {
Log.e("log_tag", "Error converting result "+e.toString());
e.printStackTrace();
}
}
}
}
}
Here is the api.php
这是 api.php
<?php
require_once("../contactdb.php");
$myusername=$_REQUEST["email"];
$mypassword=$_REQUEST["password"];
// To protect MySQL injection (more detail about MySQL injection)
$myusername = stripslashes($myusername);
$mypassword = stripslashes($mypassword);
$myusername = mysql_real_escape_string($myusername);
$mypassword = mysql_real_escape_string($mypassword);
$sql="SELECT uid,name FROM u_info WHERE email='".$myusername."' AND password ='".$mypassword."'";
$result=mysql_query($sql);
// Mysql_num_row is counting table row
$count=mysql_num_rows($result);
if($count==1){
while($row=mysql_fetch_assoc($result))
$output[]=$row;
echo json_encode($output);
mysql_close();
}else{
echo "Error Occured!";
}
?>
Finally, When I goto browser and write like this
最后，当我转到浏览器并像这样写时
http://mywebsite.com/android/[email protected]&password=1234
I got this json array!
我得到了这个 json 数组！
?[{"uid":"120","name":"MyFirstName MyLastName"}]
So Far I google, I have found different formats of json array! I found everywhere Intented Json. My json array is currently in Raw Json format. I don't find anywhere how to convert Raw Json format into Intented Json format.
到目前为止，我谷歌，我发现了不同格式的json数组！我到处都能找到 Intented Json。我的 json 数组目前是原始 Json 格式。我在任何地方都找不到如何将原始 Json 格式转换为 Intent Json 格式。
Thanks in advance guys! Any help would be appreciated! If possible, please provide the correct code!
在此先感谢各位！任何帮助，将不胜感激！如果可能，请提供正确的代码！
采纳答案by rcbevans
That is NOT valid JSON syntax:
这不是有效的 JSON 语法：
{
"employees": [
{ "firstName":"John" , "lastName":"Doe" },
{ "firstName":"Anna" , "lastName":"Smith" },
{ "firstName":"Peter" , "lastName":"Jones" }
]
}
Is Valid.
已验证。
Note: This is also valid:
注意：这也有效：
{"employees": [ { "firstName":"John" , "lastName":"Doe" }, { "firstName":"Anna" , "lastName":"Smith" }, { "firstName":"Peter" , "lastName":"Jones" } ] }
{"employees": [ { "firstName":"John" , "lastName":"Doe" }, { "firstName":"Anna" , "lastName":"Smith" }, { "firstName":"Peter" , "lastName":"Jones" } ] }
The syntax structure is the important part, not the formatting in terms of indentation.
语法结构是重要的部分，而不是缩进的格式。
As otherwise said, to use the fomat you're returning, you need to cut the substring from the response, i.e get rid of the square brackets surrounding the braces.
否则，要使用您返回的格式，您需要从响应中剪切子字符串，即去掉大括号周围的方括号。
In PHP I create a proper json response as follows:
在 PHP 中，我创建了一个正确的 json 响应，如下所示：
// array for JSON response
$response = array();
$response["apps"] = array();
$apps = array();
$apps["name"] = $row["name"];
$apps["package"] = $row["package"];
$apps["version"] = $row["version"];
$apps["dateversion"] = $row["dateversion"];
array_push($response["apps"], $apps);
$response["success"] = 1;
echo json_encode($response);
This basically gives
这基本上给
{ "success":"1", "apps":{["name":"NAME", "package":"PACKAGE", "version":"VERSION", "dateversion":"DATEVERSION"]}}
which can be parsed correctly by any of the abundant examples of JSON classes which you can make use of. Hacking and using substring to manually remove the first N characters is NOT good practice...
您可以使用任何丰富的 JSON 类示例正确解析它们。黑客攻击和使用子字符串手动删除前 N 个字符不是一个好习惯......
