您可以使用这些链接：
parse JSON in android，Android JSON Parsing Tutorial

恐怕我不能发表评论，但这个教程肯定会帮助你，简单地说，你使用HttpUrlConnection来读取JSON的页面，然后使用org.json.JSONObject来解析它。
http://ihofmann.wordpress.com/2012/08/09/restful-web-services-with-json-in-android/

这个问题是关于你是否会直接在你的设备上读取一个php或者从你的网络服务器请求它.你可以做第一个，但是你必须在你的设备上安装一个网络服务器，可能是Apache，因为“localhost and 127.0.0.1“可能没有网络服务器，你可以使用下面的类或库来从它获取数据，它可能是dam！第二个很简单，把你的php放在你的服务器上，客户端应用程序通过http/https等调用它：
1.简单连接：

public static class Connector extends AsyncTask<String, Object, Object> {
private static final int   DEFAULT_CNN_TIME_OUT = 1000 * 20;
private static String      USER_AGENT;
private static final int[] LOCK                 = new int[1];
private String             mUrl;
private byte[]             mBody;

public Connector( Context _cxt ) {
    super();
    if( TextUtils.isEmpty( USER_AGENT ) ) {
        // Without this, the default provided by API will be like "Dalvik/1.6.0 (Linux; U; Android 4.0.4; BASE_Lutea_3 Build/IMM76D)" .
        USER_AGENT = new WebView( _cxt ).getSettings().getUserAgentString();
    }
}

/*
 * Convenient function to execute the connecting task.
 */
public void submit( String _url ) {
    this.execute( _url );
}

@Override
protected Object doInBackground( String... _params ) {
    mUrl = _params[0];
    Object ret = null;
    HttpURLConnection conn = null;
    try {
        synchronized( LOCK ) {
            InputStream in = null;
            conn = connect( mUrl );
            // if we don't do conn.setRequestProperty( "Accept-Encoding", "gzip" ), the wrapper GZIPInputStream can be removed.
            onConnectorInputStream( in = new GZIPInputStream( conn.getInputStream() ) );
            in.close();
            in = null;
        }
    }
    catch( Exception _e ) {
        ret = _e;
    }
    finally {
        if( conn != null ) {
            conn.disconnect();
            conn = null;
        }
    }
    return ret;
}

@Override
protected void onPostExecute( Object _result ) {
    if( _result instanceof SocketTimeoutException ) {
        onConnectorConnectTimout();
    } else if( _result instanceof ConnectorPostConnectException ) {
        onConnectorError( ((ConnectorPostConnectException) _result).getStatus() );
    } else if( _result instanceof Exception ) {
        onConnectorInvalidConnect( (Exception) _result );
    } else if( _result == null ) {
        onConnectorFinished();
    }
    handleEstablishedConnection();
}

/*
 * Internal help and test function.
 */
private static void handleEstablishedConnection() {
    try {
        Log.v( TAG, "Connection is established." );
        CookieStore cs = CookieManager.getInstance().getCookieStore();
        if( cs != null ) {
            Log.v( TAG, "------------cookies------------" );
            List<Cookie> list = cs.getCookies();
            if( list != null && list.size() > 0 ) {
                StringBuilder cookieBuilder = new StringBuilder();
                for( Cookie c : list ) {
                    cookieBuilder
                            .append( c.getName().trim() )
                            .append( "=>" )
                            .append( c.getValue().trim() )
                            .append( "=>" )
                            .append( c.getDomain() );
                    Log.v( TAG, cookieBuilder.toString() );
                    cookieBuilder.delete( 0, cookieBuilder.length() - 1 );
                }
                cookieBuilder = null;
            } else {
                Log.v( TAG, "Empty cookies." );
            }
            cs = null;
            list = null;
        }
    }
    catch( Exception _e ) {
        Log.e( TAG, "Error in handleEstablishedConnection: " + _e.getMessage() );
    }
    finally {
    }
}

private HttpURLConnection connect( String _urlStr ) throws Exception {
    URL url = null;
    HttpURLConnection conn = null;
    try {
        try {
            url = new URL( _urlStr );
        }
        catch( MalformedURLException e ) {
            throw new IllegalArgumentException( "Invalid url: " + _urlStr );
        }
        conn = preConnect( url );
        doConnect( conn );
        conn = postConnect( conn );
    }
    catch( Exception _e ) {
        throw _e;
    }
    finally {
        url = null;
    }
    return conn;
}

private HttpURLConnection preConnect( URL url ) throws Exception {
    HttpURLConnection conn;
    conn = (HttpURLConnection) url.openConnection();
    conn.setUseCaches( false );
    // http://www.aswinanand.com/2009/01/httpurlconnectionsetfollowredirects-bug/comment-page-1/#comment-13330
    // see the url to learn more about the problem of redirect
    conn.setInstanceFollowRedirects( false );
    conn.setDoOutput( true );// allows body
    mBody = getBody();
    if( hasBody() ) {
        conn.setFixedLengthStreamingMode( mBody.length );
    }
    conn.setRequestMethod( "POST" );
    conn.setRequestProperty( "Connection", "Keep-Alive" );
    conn.setRequestProperty( "Content-Type", "application/x-www-form-urlencoded;charset=UTF-8" );
    conn.setRequestProperty( "User-Agent", USER_AGENT );
    conn.setRequestProperty( "Accept-Encoding", "gzip" );// force server to send in Content-Encoding: gzip .
    String cookies = onCookie();
    if( !TextUtils.isEmpty( cookies ) ) {
        conn.setRequestProperty( "Cookie", onCookie() );
        cookies = null;
    }
    conn.setConnectTimeout( onSetConnectTimeout() );
    return conn;
}

/*
 * Convenient function to check the exiting of body.
 */
private boolean hasBody() {
    return mBody != null && mBody.length > 0;
}

private void doConnect( HttpURLConnection conn ) throws Exception {
    OutputStream out; // the outgoing stream
    out = conn.getOutputStream();
    if( hasBody() ) {
        out.write( mBody );
    }
    out.close();
    out = null;
}

private HttpURLConnection postConnect( HttpURLConnection conn ) throws Exception {
    int status = conn.getResponseCode();
    if( status != HttpURLConnection.HTTP_OK ) {
        throw new ConnectorPostConnectException( status );
    } else {
        CookieManager.getInstance().put( conn.getURL().toURI(), conn.getHeaderFields() );
        return conn;
    }
}

private byte[] getBody() {
    byte[] body = null;
    String bodyString = onSetBody();
    if( !TextUtils.isEmpty( bodyString ) ) {
        body = bodyString.getBytes();
    }
    return body;
}

// ------------------------------------------------
// Overrides methods here
// ------------------------------------------------

protected int onSetConnectTimeout() {
    return DEFAULT_CNN_TIME_OUT;
}

protected String onCookie() {
    return null;
}

protected String onSetBody() {
    return null;
}

protected void onConnectorConnectTimout() {
    Log.e( TAG, "Handling connector timeout gracefully." );
}

protected void onConnectorError( int _status ) {
    Log.e( TAG, "Handling connector error(responsed) gracefully: " + _status );
}

protected void onConnectorInvalidConnect( Exception _e ) {
    Log.e( TAG, "Handling connector invalid connect(crash) gracefully: " + _e.toString() );
}

/*
 * Read data here. The function runs in thread. To hook on UI thread use onConnectorFinished()
 */
protected void onConnectorInputStream( InputStream _in ) {
}

/*
 * Last handler for a success connection
 */
protected void onConnectorFinished() {
}
}

1.使用齐射获得回应：https://github.com/ogrebgr/android_volley_examples/blob/master/src/com/github/volley_examples/Act_SimpleRequest.java
1.使用jsoup获取“原始html”：http://jsoup.org/

假设这是ur php文件db.php，数据库为'deal'，表为'city'，包含字段CITY_ID和CITY_NAME

<?php

$con = mysql_connect('localhost', 'root', '');

if (!$con)
{
die("could not connect: " + mysql_error());
}
mysql_select_db("deal", $con);

$result=mysql_query("SELECT * FROM city ", $con);
while ($row = mysql_fetch_assoc($result))
{
$output[]=$row;
}
print(json_encode($output));
mysql_close($con);   
?>