Android：通過url傳遞參數

Question

我想使用http發布請求將一些數據插入數據庫。 我的post.php頁面是：

      if(trim($_GET['param1'])!="" && trim($_GET['param2'])!="" && trim($_GET['param3'])!="" && trim($_GET['param4'])!="" && trim($_GET['param5'])!="")
{
    $connectionInfo = array(  "UID" => $DB_USER,  "PWD" => $DB_PASS, "Database"=>$DB_DATABASE );
    $con = sqlsrv_connect($DB_SERVER,$connectionInfo);
    if(!$con)
    {
      die('Could not connect: ' . sqlsrv_errors());
    }
    $query="INSERT INTO Table (param1,param2,param3,param4,param5) VALUES (
            '".$_GET['param1']."',
            ".$_GET['param2'].",
            ".$_GET['param3'].",
            '".$_GET['param4']."',
            ".$_GET['param5'].")";
            [...]

為了發送數據，我將所有參數附加到url，例如： http://<myip>/MySite/post.php?param2=10&param3=8&param1=2012-12-01 13:00:00&param4=Name&param5=80

一切正常，但是當我嘗試從Android應用程序發送數據時，我無法達到目標。 如何通過url傳遞數據？ 在Android中，我嘗試過：

    HttpPost httppost = new HttpPost("http://<Myip>/MySite/post.php");
    List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(5);
    nameValuePairs.add(new BasicNameValuePair("param2", "10"));
    nameValuePairs.add(new BasicNameValuePair("param3", "98"));
    nameValuePairs.add(new BasicNameValuePair("param1", "2012-12-01 13:00:00"));
    nameValuePairs.add(new BasicNameValuePair("param4", "Name"));
    nameValuePairs.add(new BasicNameValuePair("param5", "50"));
    //httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs, "UTF-8"));
    httppost.setHeader("Content-Type", "application/x-www-form-urlencoded");
    httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));  

    // Execute HTTP Post Request
    HttpResponse response = httpclient.execute(httppost)

與：

String urlParameters = "param1=2012-12-01 13:00:00&param2=b&param3=c...";
String request = "http://<Myip>/MySite/post.php";
URL url = new URL(request); 
HttpURLConnection connection = (HttpURLConnection) url.openConnection();           
connection.setDoOutput(true);
connection.setDoInput(true);
connection.setInstanceFollowRedirects(false); 
connection.setRequestMethod("POST"); 
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); 
connection.setRequestProperty("charset", "utf-8");
connection.setRequestProperty("Content-Length", ""  Integer.toString(urlParameters.getBytes().length));
connection.setUseCaches (false);
DataOutputStream wr = new DataOutputStream(connection.getOutputStream ());
wr.writeBytes(urlParameters);
wr.flush();
wr.close();
connection.disconnect();

但是我總是會出錯。 使用第二種方法，例外是：

12-17 18:08:26.617: E/AndroidRuntime(4837): FATAL EXCEPTION: main
12-17 18:08:26.617: E/AndroidRuntime(4837): android.os.NetworkOnMainThreadException
12-17 18:08:26.617: E/AndroidRuntime(4837):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:84)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.io.IoBridge.connectErrno(IoBridge.java:127)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.io.IoBridge.connect(IoBridge.java:112)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at java.net.Socket.connect(Socket.java:842)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpConnection.<init>(HttpConnection.java:77)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:351)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:86)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:308)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpEngine.connect(HttpEngine.java:303)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:282)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:232)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:80)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at libcore.net.http.HttpURLConnectionImpl.getOutputStream(HttpURLConnectionImpl.java:188)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at  com.example.applic.applic.postData(MyApp.java:197)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at com.example.applic.applic$1.run(MyApp.java:127)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at android.os.Handler.handleCallback(Handler.java:605)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at android.os.Handler.dispatchMessage(Handler.java:92)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at android.os.Looper.loop(Looper.java:137)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at android.app.ActivityThread.main(ActivityThread.java:4514)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at java.lang.reflect.Method.invokeNative(Native Method)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at java.lang.reflect.Method.invoke(Method.java:511)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
12-17 18:08:26.617: E/AndroidRuntime(4837):     at dalvik.system.NativeStart.main(Native Method)

我能做什么？

Answer 1

NetworkOnMainThreadException ：

當應用程序嘗試在其主線程上執行聯網操作時引發的異常。

意味着您正在嘗試從UI線程運行網絡操作，因此將所有與網絡相關的代碼放入AsyncTask的doInBackground方法中，並在完成doInBackground方法執行后使用onPostExecute來更新UI

並且如果您使用的是API LEVEL 9或GREATER FROM 9，則在Activity的onCreate中添加StrictMode以避免此錯誤

StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder()
                 .detectDiskReads()
                 .detectDiskWrites()
                 .detectNetwork()  
                 .penaltyLog()
                 .build());

Answer 2

您正在收到NetworkOnMainThreadException異常。 您需要將網絡請求代碼移至另一個線程或使用Asynctask。

您不能在主線程上發出網絡請求

Answer 3

當應用程序嘗試在其主線程上執行聯網操作時拋出此異常，而在android版本> = 3中是不允許的。

為了擺脫這種異常，在AsyncTask中運行代碼的更好方法是：

class BackTask extends AsyncTask<Void, Void, Void> {
    protected Void doInBackground(Void... arg) {
        //Implement Logic you want to perform in background.
    }

    protected void onPostExecute(Void feed) {
       //Implement logic whatever you want to perform after task complete.
    }
 }

new BackTask().execute();

要么

StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);