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  • Android 通过Base64上传图片到服务器

    之前做上传图片是采用HttpServlet上传,不过用了一下Base64上传图片后,感觉比HttpServlet方便很多,大家也可以跟着尝试一下。

    前台图片处理:(传Bitmap对象即可)

        /**
         * 通过Base32将Bitmap转换成Base64字符串
         * @param bit
         * @return
         */
        public String Bitmap2StrByBase64(Bitmap bit){
           ByteArrayOutputStream bos=new ByteArrayOutputStream();
           bit.compress(CompressFormat.JPEG, 40, bos);//参数100表示不压缩
           byte[] bytes=bos.toByteArray();
           return Base64.encodeToString(bytes, Base64.DEFAULT);
        }

    前台发送数据:(調用setImgByStr()方法,第一個參數imgStr 为Bitmap转成Base64的字符串,第二个参数imgName为图片的名字,包含后缀名.jpg

        public static String host = "http://192.168.1.166:8080/ImageServer/";
        
        public static String getContent(String url) throws Exception {
    
            StringBuilder sb = new StringBuilder();
     
            HttpClient client = new DefaultHttpClient();
            HttpParams httpParams = client.getParams();
            // 设置网络超时参数
            HttpConnectionParams.setConnectionTimeout(httpParams, 3000);
    
            HttpConnectionParams.setSoTimeout(httpParams, 5000);
            HttpResponse response = client.execute(new HttpGet(url));
            HttpEntity entity = response.getEntity();
            if (entity != null) {
                BufferedReader reader = new BufferedReader(new InputStreamReader(
                        entity.getContent(), "UTF-8"), 8192);
    
                String line = null;
                while ((line = reader.readLine()) != null) {
                    sb.append(line + "
    ");
                }
                reader.close();
    
            }
    
            return sb.toString();
        }
        public static HttpResponse post(Map<String, Object> params, String url) {
    
            HttpClient client = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);
            httpPost.addHeader("charset", HTTP.UTF_8);
            httpPost.setHeader("Content-Type",
                    "application/x-www-form-urlencoded; charset=utf-8");
            HttpResponse response = null;
            if (params != null && params.size() > 0) {
                List<NameValuePair> nameValuepairs = new ArrayList<NameValuePair>();
                for (String key : params.keySet()) {
                    nameValuepairs.add(new BasicNameValuePair(key, (String) params
                            .get(key)));
                }
                try {
                    httpPost.setEntity(new UrlEncodedFormEntity(nameValuepairs,
                            HTTP.UTF_8));
                    response = client.execute(httpPost);
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                } catch (ClientProtocolException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                } catch (RuntimeException e) {
                    e.printStackTrace();
                }
            } else {
                try {
                    response = client.execute(httpPost);
                } catch (ClientProtocolException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
    
            return response;
    
        }
        public static Object getValues(Map<String, Object> params, String url) {
            String token = "";
            HttpResponse response = post(params, url);
            if (response != null) {
                try {
                    token = EntityUtils.toString(response.getEntity());
                    response.removeHeaders("operator");
                } catch (ParseException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return token;
        }
        public static Object setImgByStr(String imgStr,String imgName){
            String url =  host+"channel-uploadImage.action";
            Map<String,Object> params = new HashMap<String, Object>();
            params.put("imgStr", imgStr);
            params.put("imgName", imgName);
            return getValues(params, url);
        }

    后台接收数据:

        public void uploadPhoto() {
            //获取存储路径
            HttpServletRequest request = ServletActionContext.getRequest();
            String path = ServletActionContext.getServletContext().getRealPath("/")+"upload";
            File file = new File(path);
            if(!file.exists()){
                file.mkdir();
            }
            String imgPath  = path + request.getParameter("imgName");
            String imgStr = request.getParameter("imgStr");
            boolean flag = string2Image(imgStr, imgPath);
            JacksonUtil.responseJSON(response, flag);
        }

    后台图片处理:

        /**
         * 通过BASE64Decoder解码,并生成图片
         * @param imgStr 解码后的string
         */
        public boolean string2Image(String imgStr, String imgFilePath) {
            // 对字节数组字符串进行Base64解码并生成图片
            if (imgStr == null)
                return false;
            try {
                // Base64解码
                byte[] b = new BASE64Decoder().decodeBuffer(imgStr);
                for (int i = 0; i < b.length; ++i) {
                    if (b[i] < 0) {
                        // 调整异常数据
                        b[i] += 256;
                    }
                }
                // 生成Jpeg图片
                OutputStream out = new FileOutputStream(imgFilePath);
                out.write(b);
                out.flush();
                out.close();
                return true;
            } catch (Exception e) {
                return false;
            }
        }    

    OK ! 如果成功上传前端会接收到true ,反之失败false。希望对大家有所帮助!

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  • 原文地址:https://www.cnblogs.com/zhujiabin/p/6165103.html
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