HttpURLConnection的setRequestProperty函数的作用

[002大破天幕杀机]

在android上实现了POST请求，成功上传给服务器一张图片。虽然我代码中没有用到setRequestProperty这个函数，但是不知道它的作用是什么？
代码如下：

URL url = new URL(
									"http://192.168.191.104:8080/myapp/servlet/MyServlet");
							HttpURLConnection connection = ((HttpURLConnection) url
									.openConnection());
							connection.setDoInput(true);
							connection.setDoOutput(true);
							connection.setUseCaches(false);
							connection.setRequestMethod("POST");
							connection.connect();
							OutputStream out = connection.getOutputStream();
							
							int len;
							byte[] buffer = new byte[1024];
							// 读取文件
							FileInputStream fileInputStream = new FileInputStream(
									Environment.getExternalStorageDirectory()
											.getAbsolutePath()
											+ "/123.jpg");
							while((len = fileInputStream.read(buffer, 0, 1024)) != -1){

								out.write(buffer);
							}
	
							out.flush();
							out.close();
							fileInputStream.close();

							InputStream input = connection.getInputStream();
							while ((len = input.read(buffer)) != -1) {
								Log.i("tag", "data:"
										+ new String(buffer, 0, len));
							}
							input.close();
							connection.disconnect();

[002大破天幕杀机]

服务器的代码如下：

	ServletInputStream inputStream = ((ServletRequest) request)
				.getInputStream();
		int len, offset, count;
		count = offset = 0;
		byte[] buffer = new byte[1024];

		try {
			FileOutputStream outputStream = new FileOutputStream("D:\\123.jpg");
			while ((len = inputStream.readLine(buffer, 0, 1024)) != -1) {
				offset += len;
				outputStream.write(buffer, 0, len);
			}
			outputStream.flush();
			outputStream.close();
		} catch (Exception e) {
			System.out.println(e.toString());
		}

		PrintWriter out = response.getWriter();
		out.println("ok");

[zyxel60b]

setRequestProperty主要是设置HttpURLConnection请求头里面的属性 比如Cookie、User-Agent（浏览器类型）等等，具体可以看HTTP头相关的材料 至于要设置什么这个要看服务器端的约定

[sligner]

设置头信息的，比如格式，UA等，不设置自然有默认的，一般的请求倒不需要去设置，可以去看看android里的DefaultHttpClient里也有设置头信息的

[问答小助手]

setRequestProperty 主要是用来设置下面的功能

connection.setRequestProperty("Connection", "Keep-Alive");
connection.setRequestProperty("Content-Type", "multipart/form-data;boundary="+boundary);

或者

Connection.setRequestProperty("Content-Type", "text/plain; charset=utf-8");

有时候你需要给 connection 指定 Content-type。

[常常要奋斗]

恩，3楼正解吧~

[Simple-520]

请问楼主，如何设置HTTP头 版本为HTTP2.0 ??? 急！qq:348224249

[楠楠2015]

可不可以把代码贴全啊，本人Android菜鸟，希望能多学习

[uestczhangchao]

HTTP sends such requests with a Content-Type: multipart/form-data header or a Content-Type: multipart/mixed header and a multipart body, like this: Content-Type: multipart/form-data; boundary=[abcdefghijklmnopqrstuvwxyz] where the boundary specifies the delimiter string between the different parts of the body.

[xinyu116301]

学习一下。。。。。