本文实例讲述了Android使用post方式上传图片到服务器的方法。分享给大家供大家参考，具体如下：

/**

* 上传文件到服务器类

*

* @author tom

*/

public class UploadUtil {

private static final String TAG = "uploadFile";

private static final int TIME_OUT = 10 * 1000; // 超时时间

private static final String CHARSET = "utf-8"; // 设置编码

/**

* Android上传文件到服务端

*

* @param file 需要上传的文件

* @param RequestURL 请求的rul

* @return 返回响应的内容

*/

public static String uploadFile(File file, String RequestURL) {

String result = null;

String BOUNDARY = UUID.randomUUID().toString(); // 边界标识 随机生成

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

String CONTENT_TYPE = "multipart/form-data"; // 内容类型

try {

URL url = new URL(RequestURL);

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

conn.setReadTimeout(TIME_OUT);

conn.setConnectTimeout(TIME_OUT);

conn.setDoInput(true); // 允许输入流

conn.setDoOutput(true); // 允许输出流

conn.setUseCaches(false); // 不允许使用缓存

conn.setRequestMethod("POST"); // 请求方式

conn.setRequestProperty("Charset", CHARSET); // 设置编码

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

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

if (file != null) {

/**

* 当文件不为空，把文件包装并且上传

*/

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

StringBuffer sb = new StringBuffer();

sb.append(PREFIX);

sb.append(BOUNDARY);

sb.append(LINE_END);

/**

* 这里重点注意： name里面的值为服务端需要key 只有这个key 才可以得到对应的文件

* filename是文件的名字，包含后缀名的 比如:abc.png

*/

sb.append("Content-Disposition: form-data; name=\"uploadfile\"; filename=\""

+ file.getName() + "\"" + LINE_END);

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

sb.append(LINE_END);

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

InputStream is = new FileInputStream(file);

byte[] bytes = new byte[1024];

int len = 0;

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

dos.write(bytes, 0, len);

}

is.close();

dos.write(LINE_END.getBytes());

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

dos.write(end_data);

dos.flush();

/**

* 获取响应码 200=成功 当响应成功，获取响应的流

*/

int res = conn.getResponseCode();

Log.e(TAG, "response code:" + res);

// if(res==200)

// {

Log.e(TAG, "request success");

InputStream input = conn.getInputStream();

StringBuffer sb1 = new StringBuffer();

int ss;

while ((ss = input.read()) != -1) {

sb1.append((char) ss);

}

result = sb1.toString();

Log.e(TAG, "result : " + result);

// }

// else{

// Log.e(TAG, "request error");

// }

}

} catch (MalformedURLException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

return result;

}

/**

* 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 url Service net address

* @param params text content

* @param files pictures

* @return String result of Service response

* @throws IOException

*/

public static String post(String url, 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(url);

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

conn.setReadTimeout(10 * 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=\"uploadfile\"; filename=\""

+ file.getValue().getName() + "\"" + 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();

InputStream in = conn.getInputStream();

StringBuilder sb2 = new StringBuilder();

if (res == 200) {

int ch;

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

sb2.append((char) ch);

}

}

outStream.close();

conn.disconnect();

return sb2.toString();

}

}

示例调用第二种方式上传：

final Map params = new HashMap();

params.put("send_userId", String.valueOf(id));

params.put("send_email", address);

params.put("send_name", name);

params.put("receive_email", emails);

final Map files = new HashMap();

files.put("uploadfile", file);

final String request = UploadUtil.post(requestURL, params, files);

希望本文所述对大家Android程序设计有所帮助。