android上传图片至服务器


这里举了两个例子,第一个例子比较全面,第二个例子作为入门级的。其实都是大同小异,这是我看的网上比较好的两个例子。


例一:




android studio第一次上传 android studio上传图片到服务器_android




Upload Activity:


<span style="font-size:14px;">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();
	}

}</span>

重点 UploadUtil:

<span style="font-size:14px;">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;
	}
}</span>

例二:


服务器servlet代码
publicvoid doPost(HttpServletRequest request, HttpServletResponse response)  
           throws ServletException, IOException {  
            
           String temp=request.getSession().getServletContext().getRealPath("/")+"temp";   //临时目录
           System.out.println("temp="+temp);
           String loadpath=request.getSession().getServletContext().getRealPath("/")+"Image"; //上传文件存放目录
           System.out.println("loadpath="+loadpath);
           DiskFileUpload fu =new DiskFileUpload();
           fu.setSizeMax(1*1024*1024);   // 设置允许用户上传文件大小,单位:字节
           fu.setSizeThreshold(4096);   // 设置最多只允许在内存中存储的数据,单位:字节
           fu.setRepositoryPath(temp); // 设置一旦文件大小超过getSizeThreshold()的值时数据存放在硬盘的目录
          
           //开始读取上传信息
int index=0;
           List fileItems =null;
                
                        
                                try {
                                        fileItems = fu.parseRequest(request);
                                         System.out.println("fileItems="+fileItems);
                                } catch (Exception e) {
                                        e.printStackTrace();
                                }
                        
                
           Iterator iter = fileItems.iterator(); // 依次处理每个上传的文件
while (iter.hasNext())
           {
               FileItem item = (FileItem)iter.next();// 忽略其他不是文件域的所有表单信息
if (!item.isFormField())
               {
                   String name = item.getName();//获取上传文件名,包括路径
                   name=name.substring(name.lastIndexOf("\\")+1);//从全路径中提取文件名
long size = item.getSize();
                   if((name==null||name.equals("")) && size==0)
                         continue;
                   int point = name.indexOf(".");
                   name=(new Date()).getTime()+name.substring(point,name.length())+index;
                   index++;
                   File fNew=new File(loadpath, name);
                   try {
                                        item.write(fNew);
                                } catch (Exception e) {
                                        // TODO Auto-generated catch block
                                        e.printStackTrace();
                                }
                  
                  
               }
               else//取出不是文件域的所有表单信息
               {
                   String fieldvalue = item.getString();
            //如果包含中文应写为:(转为UTF-8编码)
                   //String fieldvalue = new String(item.getString().getBytes(),"UTF-8");
               }
           }
           String text1="11";
           response.sendRedirect("result.jsp?text1="+ text1);
    }

服务器端代码


服务器servlet代码
publicvoid doPost(HttpServletRequest request, HttpServletResponse response)  
           throws ServletException, IOException {  
            
           String temp=request.getSession().getServletContext().getRealPath("/")+"temp";   //临时目录
           System.out.println("temp="+temp);
           String loadpath=request.getSession().getServletContext().getRealPath("/")+"Image"; //上传文件存放目录
           System.out.println("loadpath="+loadpath);
           DiskFileUpload fu =new DiskFileUpload();
           fu.setSizeMax(1*1024*1024);   // 设置允许用户上传文件大小,单位:字节
           fu.setSizeThreshold(4096);   // 设置最多只允许在内存中存储的数据,单位:字节
           fu.setRepositoryPath(temp); // 设置一旦文件大小超过getSizeThreshold()的值时数据存放在硬盘的目录
          
           //开始读取上传信息
int index=0;
           List fileItems =null;
                
                        
                                try {
                                        fileItems = fu.parseRequest(request);
                                         System.out.println("fileItems="+fileItems);
                                } catch (Exception e) {
                                        e.printStackTrace();
                                }
                        
                
           Iterator iter = fileItems.iterator(); // 依次处理每个上传的文件
while (iter.hasNext())
           {
               FileItem item = (FileItem)iter.next();// 忽略其他不是文件域的所有表单信息
if (!item.isFormField())
               {
                   String name = item.getName();//获取上传文件名,包括路径
                   name=name.substring(name.lastIndexOf("\\")+1);//从全路径中提取文件名
long size = item.getSize();
                   if((name==null||name.equals("")) && size==0)
                         continue;
                   int point = name.indexOf(".");
                   name=(new Date()).getTime()+name.substring(point,name.length())+index;
                   index++;
                   File fNew=new File(loadpath, name);
                   try {
                                        item.write(fNew);
                                } catch (Exception e) {
                                        // TODO Auto-generated catch block
                                        e.printStackTrace();
                                }
                  
                  
               }
               else//取出不是文件域的所有表单信息
               {
                   String fieldvalue = item.getString();
            //如果包含中文应写为:(转为UTF-8编码)
                   //String fieldvalue = new String(item.getString().getBytes(),"UTF-8");
               }
           }
           String text1="11";
           response.sendRedirect("result.jsp?text1="+ text1);
    }