Android 上传图片到服务器

界面很简单，点击 【选择图片】，从图库里选择图片，显示到下面的imageview里，点击上传，就会上传到指定的服务器

布局文件：

    <?xml version="1.0" encoding="utf-8"?>        <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"            android:orientation="vertical"            android:layout_width="fill_parent"            android:layout_height="fill_parent"            >            <Button              android:layout_width="fill_parent"             android:layout_height="wrap_content"             android:text="选择图片"            android:id="@+id/selectImage"            />            <Button              android:layout_width="fill_parent"             android:layout_height="wrap_content"             android:text="上传图片"            android:id="@+id/uploadImage"            />             <ImageView              android:layout_width="wrap_content"             android:layout_height="wrap_content"             android:id="@+id/imageView"            />        </LinearLayout>  

public class Upload extends Activity implements OnClickListener {   private static String requestURL = "http://192.168.1.212:8011/pd/upload/fileUpload.do";   private Button selectImage, uploadImage;   private ImageView imageView;     private String picPath = null;     /** Called when the activity is first created. */   @Override   public void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.upload);      selectImage = (Button) this.findViewById(R.id.selectImage);    uploadImage = (Button) this.findViewById(R.id.uploadImage);    selectImage.setOnClickListener(this);    uploadImage.setOnClickListener(this);      imageView = (ImageView) this.findViewById(R.id.imageView);     }     @Override   public void onClick(View v) {    switch (v.getId()) {    case R.id.selectImage:     /***      * 这个是调用android内置的intent，来过滤图片文件 ，同时也可以过滤其他的      */     Intent intent = new Intent();     intent.setType("image/*");     intent.setAction(Intent.ACTION_GET_CONTENT);     startActivityForResult(intent, 1);     break;    case R.id.uploadImage:     if (picPath == null) {        Toast.makeText(Upload.this, "请选择图片！", 1000).show();     } else {      final File file = new File(picPath);        if (file != null) {       String request = UploadUtil.uploadFile(file, requestURL);       uploadImage.setText(request);      }     }     break;    default:     break;    }   }     @Override   protected void onActivityResult(int requestCode, int resultCode, Intent data) {    if (resultCode == Activity.RESULT_OK) {     /**      * 当选择的图片不为空的话，在获取到图片的途径      */     Uri uri = data.getData();     Log.e(TAG, "uri = " + uri);     try {      String[] pojo = { MediaStore.Images.Media.DATA };        Cursor cursor = managedQuery(uri, pojo, null, null, null);      if (cursor != null) {       ContentResolver cr = this.getContentResolver();       int colunm_index = cursor         .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);       cursor.moveToFirst();       String path = cursor.getString(colunm_index);       /***        * 这里加这样一个判断主要是为了第三方的软件选择，比如：使用第三方的文件管理器的话，你选择的文件就不一定是图片了，        * 这样的话，我们判断文件的后缀名 如果是图片格式的话，那么才可以        */       if (path.endsWith("jpg") || path.endsWith("png")) {        picPath = path;        Bitmap bitmap = BitmapFactory.decodeStream(cr          .openInputStream(uri));        imageView.setImageBitmap(bitmap);       } else {        alert();       }      } else {       alert();      }       } catch (Exception e) {     }    }      super.onActivityResult(requestCode, resultCode, data);   }     private void alert() {    Dialog dialog = new AlertDialog.Builder(this).setTitle("提示")      .setMessage("您选择的不是有效的图片")      .setPositiveButton("确定", new DialogInterface.OnClickListener() {       public void onClick(DialogInterface dialog, int which) {        picPath = null;       }      }).create();    dialog.show();   }    }

这个才是重点 UploadUtil:

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   /**    * 上传文件到服务器    * @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 int uploadFile(File file, String RequestURL) {    int res=0;    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) {      /**       * 当文件不为空时执行上传       */      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里面的值为服务器端需要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       */        sb.append("Content-Disposition: form-data; name=\"file\"; 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       */       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 res;   }  }