/**
 * 照片轉byte二進位制
 * @param imagepath 需要轉byte的照片路徑
 * @return 已經轉成的byte
 * @throws Exception
 */
public static byte[] readStream(String imagepath) throws Exception {
FileInputStream fs = new FileInputStream(imagepath);
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = 0;
while (-1 != (len = fs.read(buffer))) {
outStream.write(buffer, 0, len);
}
outStream.close();
fs.close();
return outStream.toByteArray();
} 
 

  params.add("img", String.valueOf(readStream(img)));