发布于 2017-09-14 04:54:54 | 173 次阅读 | 评论: 0 | 来源: 网友投递
Android移动端操作系统
Android是一种基于Linux的自由及开放源代码的操作系统，主要使用于移动设备，如智能手机和平板电脑，由Google公司和开放手机联盟领导及开发。尚未有统一中文名称，中国大陆地区较多人使用“安卓”或“安致”。
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<String, String> params, Map<String, File> 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<String, String> 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<String, File> 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<String, String> params = new HashMap<String, String>();
params.put("send_userId", String.valueOf(id));
params.put("send_email", address);
params.put("send_name", name);
params.put("receive_email", emails);
final Map<String, File> files = new HashMap<String, File>();
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。