在android項目中，很多情況下上傳頭像的需求，像qq，新浪微博，微信，飛信等很多應用都有這樣的功能。

之前我寫過的兩篇文章：andorid下從相冊選取/拍照選取一張相片並剪切和android下Bitmap和base64之間的轉換把他們綜合起來，就可以來實現頭像從相冊/拍照選取,後裁剪再上傳的功能

完整源碼下載

這裡我只貼出上傳圖片的方法代碼，至於怎麼獲取到獲取到圖片，請看andorid下從相冊選取/拍照選取一張相片並剪切

/*
	 * 上傳圖片
	 */
	public void upload(View view) {
		try {
			ByteArrayOutputStream out = new ByteArrayOutputStream();
			bitmap.compress(Bitmap.CompressFormat.JPEG, 100, out);
			out.flush();
			out.close();
			byte[] buffer = out.toByteArray();

			byte[] encode = Base64.encode(buffer, Base64.DEFAULT);
			String photo = new String(encode);

			RequestParams params = new RequestParams();
			params.put("photo", photo);
			String url = "http://110.65.99.66:8080/jerry/UploadImgServlet";

			AsyncHttpClient client = new AsyncHttpClient();
			client.post(url, params, new AsyncHttpResponseHandler() {
				@Override
				public void onSuccess(int statusCode, Header[] headers,
						byte[] responseBody) {
					try {
						if (statusCode == 200) {

							Toast.makeText(MainActivity.this, "頭像上傳成功!", 0)
									.show();
						} else {
							Toast.makeText(MainActivity.this,
									"網絡訪問異常，錯誤碼：" + statusCode, 0).show();

						}
					} catch (Exception e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
				}

				@Override
				public void onFailure(int statusCode, Header[] headers,
						byte[] responseBody, Throwable error) {
					Toast.makeText(MainActivity.this,
							"網絡訪問異常，錯誤碼  > " + statusCode, 0).show();

				}
			});

		} catch (Exception e) {
			e.printStackTrace();
		}
	}

從上邊代碼可以看出，又用到我鐘愛的android-async-http 安卓異步http框架來訪問網絡

這樣一操作，圖片就會按Base64編碼格式傳送到服務器，而服務器端的代碼也是非常簡單的

package com.jerry.servlet;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.sun.org.apache.xml.internal.security.exceptions.Base64DecodingException;
import com.sun.org.apache.xml.internal.security.utils.Base64;

public class UploadImgServlet extends HttpServlet {

	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		request.setCharacterEncoding("utf-8");
		response.setCharacterEncoding("utf-8");
		response.setContentType("text/html");
		String photo = request.getParameter("photo");
		try {
			// 對base64數據進行解碼
			byte[] decode = Base64.decode(photo);
			File file = new File("e:\\decode.jpg");
			if(!file.exists()) {
				file.createNewFile();
			}
			FileOutputStream out = new FileOutputStream(file);
			out.write(decode);
			out.flush();
			out.close();
		} catch (Base64DecodingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

	}

	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		this.doGet(request, response);
	}

}

這樣圖片就成功的保存帶E盤下