使用AngularJS上传文件

这是我的HTML表单:

<form name="myForm" ng-submit="">
    <input ng-model='file' type="file"/>
    <input type="submit" value='Submit'/>
</form>

我想从本地机器上传一个图像，并想读取上传文件的内容。所有这些我都想用AngularJS来做。

当我试图打印$scope的值时。文件是未定义的。

当前回答

最简单的是使用HTML5 API，即FileReader

HTML非常简单:

<input type="file" id="file" name="file"/>
<button ng-click="add()">Add</button>

在你的控制器中定义'add'方法:

$scope.add = function() {
    var f = document.getElementById('file').files[0],
        r = new FileReader();

    r.onloadend = function(e) {
      var data = e.target.result;
      //send your binary data via $http or $resource or do anything else with it
    }

    r.readAsBinaryString(f);
}

浏览器兼容性

桌面浏览器

Edge 12, Firefox(Gecko) 3.6(1.9.2)， Chrome 7, Opera* 12.02, Safari 6.0.2

移动浏览器

Firefox(壁虎)32, Chrome 3, 歌剧* 11.5, Safari 6.1

注意:readAsBinaryString()方法已弃用，应该使用readAsArrayBuffer()代替。

2014-03-20 16:08:01

其他回答

app.directive('ngUpload', function () {   
  return {    
    restrict: 'A',  
    link: function (scope, element, attrs) {

      var options = {};
      options.enableControls = attrs['uploadOptionsEnableControls'];

      // get scope function to execute on successful form upload
      if (attrs['ngUpload']) {

        element.attr("target", "upload_iframe");
        element.attr("method", "post");

        // Append a timestamp field to the url to prevent browser caching results
        element.attr("action", element.attr("action") + "?_t=" + new Date().getTime());

        element.attr("enctype", "multipart/form-data");
        element.attr("encoding", "multipart/form-data");

        // Retrieve the callback function
        var fn = attrs['ngUpload'].split('(')[0];
        var callbackFn = scope.$eval(fn);
        if (callbackFn == null || callbackFn == undefined || !angular.isFunction(callbackFn))
        {
          var message = "The expression on the ngUpload directive does not point to a valid function.";
          // console.error(message);
          throw message + "\n";
        }                      

        // Helper function to create new  i frame for each form submission
        var addNewDisposableIframe = function (submitControl) {
          // create a new iframe
          var iframe = $("<iframe id='upload_iframe' name='upload_iframe' border='0' width='0' height='0' style='width: 0px; height: 0px;
border: none; display: none' />");

          // attach function to load event of the iframe
          iframe.bind('load', function () {

              // get content - requires jQuery
              var content = iframe.contents().find('body').text();

              // execute the upload response function in the active scope
              scope.$apply(function () { callbackFn(content, content !== "" /* upload completed */); });

              // remove iframe
              if (content != "") // Fixes a bug in Google Chrome that dispose the iframe before content is ready.
                setTimeout(function () { iframe.remove(); }, 250);


              submitControl.attr('disabled', null);
              submitControl.attr('title', 'Click to start upload.');
            });

          // add the new iframe to application
          element.parent().append(iframe);
        };

        // 1) get the upload submit control(s) on the form (submitters must be decorated with the 'ng-upload-submit' class)
        // 2) attach a handler to the controls' click event
        $('.upload-submit', element).click(
          function () {

            addNewDisposableIframe($(this) /* pass the submit control */);

            scope.$apply(function () { callbackFn("Please wait...", false /* upload not completed */); });



            var enabled = true;
            if (options.enableControls === null || options.enableControls === undefined || options.enableControls.length >= 0) {
              // disable the submit control on click
              $(this).attr('disabled', 'disabled');
              enabled = false;
            }

            $(this).attr('title', (enabled ? '[ENABLED]: ' : '[DISABLED]: ') + 'Uploading, please wait...');

            // submit the form
            $(element).submit();
          }
        ).attr('title', 'Click to start upload.');
      }
      else
        alert("No callback function found on the ngUpload directive.");     
    }   
  }; 
});



<form class="form form-inline" name="uploadForm" id="uploadForm"
ng-upload="uploadForm12"  action="rest/uploadHelpFile"  method="post"
enctype="multipart/form-data" style="margin-top: 3px;margin-left:
6px"> <button type="submit" id="mbUploadBtn" class="upload-submit"
ng-hide="true"></button> </form>

@RequestMapping(value = "/uploadHelpFile", method =
RequestMethod.POST)   public @ResponseBody String
uploadHelpFile(@RequestParam(value = "file") CommonsMultipartFile[]
file,@RequestParam(value = "fileName") String
fileName,@RequestParam(value = "helpFileType") String
helpFileType,@RequestParam(value = "helpFileName") String
helpFileName) { }

2017-11-01 03:32:10

<input type=file>元素默认不使用ng-model指令。它需要一个自定义指令:

使用ng-model1的select-ng-files指令的工作演示

angular.module("app",[]); angular.module("app").directive("selectNgFiles", function() { return { require: "ngModel", link: function postLink(scope,elem,attrs,ngModel) { elem.on("change", function(e) { var files = elem[0].files; ngModel.$setViewValue(files); }) } } }); <script src="//unpkg.com/angular/angular.js"></script> <body ng-app="app"> <h1>AngularJS Input `type=file` Demo</h1> <input type="file" select-ng-files ng-model="fileList" multiple> <h2>Files</h2> <div ng-repeat="file in fileList"> {{file.name}} </div> </body>

美元http。从FileList中post

$scope.upload = function(url, fileList) {
    var config = { headers: { 'Content-Type': undefined },
                   transformResponse: angular.identity
                 };
    var promises = fileList.map(function(file) {
        return $http.post(url, file, config);
    });
    return $q.all(promises);
};

当发送带有File对象的POST时，重要的是设置'Content-Type': undefined。然后XHR发送方法将检测File对象并自动设置内容类型。

2017-08-09 21:14:07

简单的指令

Html:

<input type="file" file-upload multiple/>

JS:

app.directive('fileUpload', function () {
return {
    scope: true,        //create a new scope
    link: function (scope, el, attrs) {
        el.bind('change', function (event) {
            var files = event.target.files;
            //iterate files since 'multiple' may be specified on the element
            for (var i = 0;i<files.length;i++) {
                //emit event upward
                scope.$emit("fileSelected", { file: files[i] });
            }                                       
        });
    }
};

在指令中，我们确保创建了一个新的作用域，然后监听对文件输入元素所做的更改。当检测到更改时，以文件对象作为参数向所有祖先作用域(向上)发出事件。

在你的控制器中:

$scope.files = [];

//listen for the file selected event
$scope.$on("fileSelected", function (event, args) {
    $scope.$apply(function () {            
        //add the file object to the scope's files collection
        $scope.files.push(args.file);
    });
});

然后在ajax调用中:

data: { model: $scope.model, files: $scope.files }

http://shazwazza.com/post/uploading-files-and-json-data-in-the-same-request-with-angular-js/

2015-02-03 10:21:17

你可以使用一个安全快速的FormData对象:

// Store the file object when input field is changed
$scope.contentChanged = function(event){
    if (!event.files.length)
        return null;

    $scope.content = new FormData();
    $scope.content.append('fileUpload', event.files[0]); 
    $scope.$apply();
}

// Upload the file over HTTP
$scope.upload = function(){
    $http({
        method: 'POST', 
        url: '/remote/url',
        headers: {'Content-Type': undefined },
        data: $scope.content,
    }).success(function(response) {
        // Uploading complete
        console.log('Request finished', response);
    });
}

2015-07-12 00:00:34