Opret forbindelse til en ekstern MySQL-database ved hjælp af Android

Android app side:

private ArrayList<String> receiveData(String file, ArrayList<NameValuePair> data)
{
    InputStream is = null;
    ArrayList<String> output = new ArrayList<String>();
    String line = null;

    //Connect and obtain data via HTTP.
    try
    {
        HttpClient httpclient = new DefaultHttpClient();
        HttpPost httppost = new HttpPost("http://www.blah.com/"+file);
        httppost.setEntity(new UrlEncodedFormEntity(data));
        HttpResponse response = httpclient.execute(httppost);
        HttpEntity entity = response.getEntity();
        is = entity.getContent();

    }
    catch(Exception e)
    {
        Log.e("log_tag", "Error in http connection "+e.toString());
    }

    //Parse data into ArrayList and return.
    try
    {
        BufferedReader reader = 
            new BufferedReader(new InputStreamReader(is,"iso-8859-1"));

        while ((line = reader.readLine()) != null) 
        {
            //Parse data into tokens and removing unimportant tokens.
            StringTokenizer st = new StringTokenizer(line, delims, false);

            while(st.hasMoreTokens())
            {
                String token = st.nextToken();
                output.add(token);
            }
        }

        is.close();
        //Log output of data in LogCat.
        Log.d("DATA","DATA:"+output);

    }
    catch(Exception e)
    {
        Log.e("log_tag", "Error converting result "+e.toString());
    }
    return output;
}

/**
 * Gets all  data from GetAllData.php
 * @return output - ArrayList containing  data.
 */
public ArrayList<String> getAllData(String row)
{
    fileName = "GetAllData.php";

    //Add arguments to arrayList<NameValuePairs> so we can encode the data and send it on.
    ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(1);
    nameValuePairs.add(new BasicNameValuePair("row", row));

    ArrayList<String> output = this.receiveData(fileName, nameValuePairs);
    return output;
}

Serverside:

så GetAllData.php-filen på serveren er:

<?php
/*
 * What this file does is it:
 * 1) Creates connection to database.
 * 2) Gets data from database.
 * 3) Encodes data to JSON. So this data can then be used by Android Application.
 * 4) Close database connection.
 */
 require_once $_SERVER['DOCUMENT_ROOT'].'/Clarity/Connection.php';
 require_once $_SERVER['DOCUMENT_ROOT'].'/Clarity/ReceiveAPI.php';

 $server = new Connection();
 $receive = new ReceiveAPI();

 //Retrieve information.
 $row = $_POST['row'];

//Connect to database.
$server->connectDB();
$output = $receive->getAllData($row); //basically method to query database.
print(json_encode($output)); //output is result of the query given back to app.

//Disconnect from database.
$server->disconnectDB();
?>

Dette er et eksempel, jeg brugte for nylig. Bare at bemærke i php-filen. Jeg importerer Connection.phpthis handler kun om forbindelsen til databasen. Så bare udskift det med din kode for at oprette forbindelse til MYSQL db. Jeg importerede også SendAPI.php (som du bare kan ignorere) Dette var bare min klasse til at sende data. Grundlæggende indeholdt den nogle af de forespørgsler, jeg ville bruge. Såsom sendAccelerationData(). Grundlæggende svarede klassen til den for lagrede procedurer.

Hvordan jeg oprettede forbindelse til databasen var i min Connection.php-klasse.

//Connect to a database.
public function connectDB()
{
    //Connect to SQL server.
    $this->connection = mysql_connect($this->hostName,$this->user,$this->password);

    if (!$this->connection) 
    {
        die('Could not connect: ' . mysql_error());
    }
    //Print("Connected to MySQL. </br>");

    //Select Database to query.
    $db_selected = mysql_select_db($this->database);
    if (!$db_selected) 
    {
        die('Could not select database' . mysql_error());
    }
    //Print("Database \"$this->database\" selected. </br>");
}

//Disconnect from database.
public function disconnectDB() 
{
    mysql_close($this->connection);
}
}

Bemærk i fejlmeddelelser, at jeg udskrev skema ud db såsom db navn/tabelnavn. Dette var blot fejlfinding. Jeg fraråder dette. DU ØNSKER IKKE at vise disse oplysninger til brugeren.