AngularJS上传文件

使用AngularJS上传文件

• 前台是Angular页面
• 后台使用SpringBoot/SpirngMVC

上传文件

• html

<div>
    <input id="fileUpload" type="file" />
    <button ng-click="uploadFile()">上传</button>
</div>

• js

$scope.upload = function(){
            var form = new FormData();
            var file = document.getElementById("fileUpload").files[0];
            fd.append('file',file);
            $http({
                method: 'POST',url: '/upload',data: form,headers: {'Content-Type': undefined},transformRequest: angular.identity
            }).success(function (data) {
                console.log('upload success');
            }).error(function (data) {
                 console.log('upload fail');
            })
        }

注意：

• AngularJS默认的'Content-Type'是application/json ，通过设置'Content-Type': undefined，这样浏览器不仅帮我们把Content-Type 设置为 multipart/form-data，还填充上当前的boundary，
• 如果手动设置为：'Content-Type': multipart/form-data，后台会抛出异常：the request was rejected because no multipart boundary was found
• boundary 是随机生成的字符串，用来分隔文本的开始和结束
• 通过设置 transformRequest: angular.identity ，anjularjs transformRequest function 将序列化我们的formdata object，也可以不添加

• 后台

@RequestMapping("/upload")
    public void uploadFile(@RequestParam(value = "file",required = true) MultipartFile file) {
        //deal with file
    }

注意

• 文件必须通过@RequestParam注解来获取，且需指定value才能获取到

• 这样就完成了上传文件

上传文件的同时传递其他参数

• html

<div>
        <input id="fileUpload" type="file" />
        <button ng-click="ok()">上传</button><br>
        <input ng-model="user.username" />
        <input ng-model="user.password" />
    </div>

• js

$scope.ok = function () {
        var form = new FormData();
        var file = document.getElementById("fileUpload").files[0];   
        var user =JSON.stringify($scope.user);

        form.append('file',file);
        form.append('user',user);

        $http({
            method: 'POST',url: '/addUser',transformRequest: angular.identity
        }).success(function (data) {
            console.log('operation success');
        }).error(function (data) {
            console.log('operation fail');
        })
    };

• 注意
  
  • 需要将Object转为String后在附加到form上，否则会直接被转为字符串[Object,object]

• 后台

@RequestMapping("/upload")
    public Map<String,Object> upload(@RequestParam(value = "file") MultipartFile file,@RequestParam(value = "user",required = true) String user) {

        try (FileInputStream in = (FileInputStream) headImg.getInputStream();
             FileOutputStream out = new FileOutputStream("filePathAndName")) {

            //将Json对象解析为UserModel对象
            ObjectMapper objectMapper = new ObjectMapper();
            UserModel userModel = objectMapper.readValue(user,UserModel.class);

            //保存文件到filePathAndName
            int hasRead = 0;
            byte[] bytes = new byte[1024];
            while ((hasRead = in.read(bytes)) > 0) {
                out.write(bytes,0,hasRead);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

注意

• ObjectMapper为com.fasterxml.jackson.databind.ObjectMapper