Android Internet access, get, post, and other methods

1. Code for checking the network status

ConnectivityManager cm = (ConnectivityManager) Context. getSystemService (Context. CONNECTIVITY_SERVICE );

NetworkInfo netInfo = cm. getActivityNetworkInfo ();

NetInfo. toString ();

2. Use Network Permissions

<Uses-permission android: name = "android. permission. INTERNET"/>

3. Get data (text and images) through URL + HttpURLConnection)

URL url = new URL ("http://www.sohu.com ");

HttpURLConnection conn = (HttpURLConnectioni) url. openConnection ();

Conn. setConnectionTimeout (5*1000 );

Conn. setRequestMethod ("GET ");

Conn. getResponseMethod ("GET ");

(Conn. getResponseCode ()! = 200) throw ...;

InputStream is = conn. getInputStream ();

String result = readData (is, "GEK ");

Conn. disconnect ();

// Obtain the image.

1. Send name-value pairs in GET Mode

// Http: // xxxx/xxx. action? Name = tom & age = 12

URL realUrl = new URL (requestUrl );

HttpURLConnection conn = (HttpURLConnection) realUrl. openConnection ();

Conn. setRequestMethod ("GET ");

Conn. setConnectionTimeout (5000 );

// Data is sent to the server until this time

If (conn. getResponseCode () = 200 ){

String result = readAsString (conn. getInputStream (), "UTF-8 ");

OutStream. close ();

System. out. println (result );

}

Note: Chinese garbled characters.

// UTF-8 indicates the server-side Encoding

1. If the get method is used to send Chinese characters, transcoding is required. UrlEncode ("Chinese", "UTF-8 ");

2. transcode the tomcat client (get mode ).

If ("GET". equals (request. getMethod ())){

String v = request. getParameter ("name ");

New String (v. getBytes ("ISO8859-1"), "UTF-8 ");

}

1. POST sends common text content

URL realUrl = new URL (requestUrl );

HttpURLConncection conn = (HttpURLConnection) realUrl. openConnection ();

Conn. setDoOutput (true );

Conn. setUseCaches (false );

Conn. setUseCaches (false );

Conn. setRequestMethod ();

Conn. setRequestProperty ("Connection", "Keep-Alive"); // maintain a persistent Connection

Conn. setRequestProperty ("Charset", "UTF-8 ");

Con. setRequestProperty ("Content-Length", String. valueOf (data. length ));

Con. setRequestProperty ("Content-Type", "application/x-www-form-urlencoded ");

String str = "name = xxx & age = 12 ";

Con. getOutputStream (). write (str. getBytes );

If (conn. getOutputStream (). write (Str. getBytes )){

If (conn. getResponseCode () = 200 ){

String result = readAsString (conn. getInputStream (), "UTF-8 ");

OutStream. close ();

System. out. println (result ):

}

}

1. POST sends xml

StringBuilder xml = new StringBuilder ();

Xml. append ("<? Xml version = \ "1.0 \" encoding = \ "UTF-8 \"?> ");

Xml. append ("<M1 V = 10000> ");

Xml. append ("<u I = 1 D = \" N73 \ "> China </U> ");

Xml. append ("</M1> ");

Byte [] xmlbyte = xml. toString (). getBytes ("UTF-8 ");

URL url = new URL ("http://xxx.do? Method = readxml ");

HttpURLConnection conn = (HttpURLConnection) url. openConnection ();

Conn. setConnectTimeout (5*1000 );

Conn. setDoOutput (true); // allow output

Conn. setUseCaches (false); // No Cache is used.

Conn. setRequestMethod ("POST ");

Conn. setRequestProperty ("Connection", "Keep-Alive"); // maintain a persistent Connection

Conn. setRequestProperty ("Charset", "UTF-8 ");

Conn. setRequestProperty ("Content-Length", String. valueOf (xmlbyte. length ));

// You must set the content type. Otherwise, the server cannot recognize the Data Type .www.2cto.com.

Conn. setRequestProperty ("Content-Type", "text/xml; charset = UTF-8 ");

DataOutputStream outStream = new DataOutputStream (conn. getOutputStream ());

OutStream. write (xmlbyte); // send xml data

OutStream. flush ();
Author: to1297488504