android 上传字符串,Android中发送Http请求(包括文件上传、servlet接收)的实例代码...

/**

* 通过拼接的方式构造请求内容，实现参数传输以及文件传输

* @param actionUrl

* @param params

* @param files

* @return

* @throws IOException

*/

public static String post(String actionUrl, Map params,

Map files) throws IOException {

String BOUNDARY = java.util.UUID.randomUUID().toString();

String PREFIX = "--" , LINEND = "\r\n";

String MULTIPART_FROM_DATA = "multipart/form-data";

String CHARSET = "UTF-8";

URL uri = new URL(actionUrl);

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

conn.setReadTimeout(5 * 1000); // 缓存的最长时间

conn.setDoInput(true);// 允许输入

conn.setDoOutput(true);// 允许输出

conn.setUseCaches(false); // 不允许使用缓存

conn.setRequestMethod("POST");

conn.setRequestProperty("connection", "keep-alive");

conn.setRequestProperty("Charsert", "UTF-8");

conn.setRequestProperty("Content-Type", MULTIPART_FROM_DATA + ";boundary=" + BOUNDARY);

// 首先组拼文本类型的参数

StringBuilder sb = new StringBuilder();

for (Map.Entry entry : params.entrySet()) {

sb.append(PREFIX);

sb.append(BOUNDARY);

sb.append(LINEND);

sb.append("Content-Disposition: form-data; name=\"" + entry.getKey() + "\"" + LINEND);

sb.append("Content-Type: text/plain; charset=" + CHARSET+LINEND);

sb.append("Content-Transfer-Encoding: 8bit" + LINEND);

sb.append(LINEND);

sb.append(entry.getValue());

sb.append(LINEND);

}

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

outStream.write(sb.toString().getBytes());

// 发送文件数据

if(files!=null)

for (Map.Entry file: files.entrySet()) {

StringBuilder sb1 = new StringBuilder();

sb1.append(PREFIX);

sb1.append(BOUNDARY);

sb1.append(LINEND);

sb1.append("Content-Disposition: form-data; name=\"file\"; filename=\""+file.getKey()+"\""+LINEND);

sb1.append("Content-Type: application/octet-stream; charset="+CHARSET+LINEND);

sb1.append(LINEND);

outStream.write(sb1.toString().getBytes());

InputStream is = new FileInputStream(file.getValue());

byte[] buffer = new byte[1024];

int len = 0;

while ((len = is.read(buffer)) != -1) {

outStream.write(buffer, 0, len);

}

is.close();

outStream.write(LINEND.getBytes());

}

//请求结束标志

byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINEND).getBytes();

outStream.write(end_data);

outStream.flush();

// 得到响应码

int res = conn.getResponseCode();

if (res == 200) {

InputStream in = conn.getInputStream();

int ch;

StringBuilder sb2 = new StringBuilder();

while ((ch = in.read()) != -1) {

sb2.append((char) ch);

}

}

outStream.close();

conn.disconnect();

return in.toString();

}