1、检测网络状态的代码
ConnectivityManager cm = (ConnectivityManager) Context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActivityNetworkInfo();
netInfo.toString();
2.使用网络权限
<uses-permission android:name="android.permission.INTERNET"/>
3.通过URL + HttpURLConnection获得数据（文本和图片）
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();
//获取图片同上
1.GET方式发送name-value对
//http://xxxx/xxx.action?name=tom&&age=12
URL realUrl = new URL(requestUrl);
HttpURLConnection conn = (HttpURLConnection) realUrl.openConnection();
conn.setRequestMethod("GET");
conn.setConnectionTimeout(5000);
//直到此时,数据才发往服务器
if( conn.getResponseCode() == 200 ){
String result = readAsString(conn.getInputStream(), "UTF-8");
outStream.close();
System.out.println(result);
}
注:中文乱码问题.
//utf-8指服务器端编码
1.get方式发送中文需要转码.UrlEncode("中文","utf-8");
2.tomcat器端需要转码(get方式).
if("GET".equals(request.getMethod())){
String v =request.getParameter("name");
new String(v.getBytes("ISO8859-1"),"UTF-8");
}
1.POST发送普通文本内容
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");//维持长连接
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发送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\">中国</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);//允许输出
conn.setUseCaches(false);//不使用Cache
conn.setRequestMethod("POST");
conn.setRequestProperty("Connection", "Keep-Alive");//维持长连接
conn.setRequestProperty("Charset", "UTF-8");
conn.setRequestProperty("Content-Length", String.valueOf(xmlbyte.length));
//必须设置内容类型,否则服务器无法识别数据类型.
conn.setRequestProperty("Content-Type", "text/xml; charset=UTF-8");
DataOutputStream outStream = new DataOutputStream(conn.getOutputStream());
outStream.write(xmlbyte);//发送xml数据
outStream.flush();
