AngularJS 使用 ng-upload 上传图片

Question

我正在尝试使用 ng-upload 在 AngularJS 中上传文件，但我遇到了问题。我的 html 看起来像这样：

<div class="create-article" ng-controller="PostCreateCtrl">
        <form ng-upload method="post" enctype="multipart/form-data" action="/write" >
            <fieldset>
                <label>Category</label>
                <select name="category_id" class="">
                    <option value="0">Select A Category</option>
                    <?php foreach($categories as $category): ?>
                        <option value="<?= $category -> category_id; ?>"><?= $category -> category_name; ?></option>
                    <?php endforeach; ?>
                </select>

                <label>Title</label>
                <input type="text" class="title span5" name="post_title"
                       placeholder="A catchy title here..."
                       value="<?= $post -> post_title; ?>" />

                <label>Attach Image</label>
                <input type="file" name="post_image" />

                 <a href='javascript:void(0)'  class="upload-submit: uploadPostImage(contents, completed)" >Crop Image</a>

                <label>Body</label>
                <div id="container">
                <textarea id="mytextarea" wrap="off" name="post_content" class="span7" placeholder="Content..."><?= $post -> post_content; ?></textarea>
                </div>
                <div style='clear:both;'></div>
                <label>Preview</label>
                <div id='textarea-preview'></div>

            </fieldset>
            <div class="span7" style="margin: 0;">
                <input type="submit" class="btn btn-success" value="Create Post" />
            <input type="submit" class="btn btn-warning pull-right draft" value="Save as Draft" />
            </div>

        </form>
    </div>

而我的 js 控制器是这样的：

ClabborApp.controller("PostCreateCtrl", ['$scope', 'PostModel',
function($scope, PostModel) {

    $scope.uploadPostImage = function(contents, completed) {
        console.log(completed);
        alert(contents);
    }

}]);

我面临的问题是当裁剪图像被点击并执行uploadPostImage时，它会上传整个表单。不是想要的行为，但我可以让它工作。最大的问题是在 js 中，函数 uploadPostImage 'contents' 参数始终未定义，即使 'completed' 参数返回为 true。

我们的目标是只上传一张图片进行裁剪。在这个过程中我做错了什么？

Answer 1

几乎没有关于上传文件的 Angular 文档。许多解决方案需要自定义指令其他依赖项（primis中的jquery ...只是为了上传文件...）。经过多次尝试后，我发现只有 angularjs（在 v.1.0.6 上测试）

html

<input type="file" name="file" onchange="angular.element(this).scope().uploadFile(this.files)"/>

Angularjs (1.0.6) 不支持“输入文件”标签上的 ng-model ，因此您必须以“本机方式”来传递所有（最终）选定的文件来自用户。

控制器

$scope.uploadFile = function(files) {
    var fd = new FormData();
    //Take the first selected file
    fd.append("file", files[0]);

    $http.post(uploadUrl, fd, {
        withCredentials: true,
        headers: {'Content-Type': undefined },
        transformRequest: angular.identity
    }).success( ...all right!... ).error( ..damn!... );

};

很酷的部分是 undefined 内容类型和 transformRequest: angular.identity 让 $http 能够选择正确的“内容类型”并管理处理多部分数据时所需的边界。

Answer 2

你可以试试ng-file-upload angularjs 插件（而不是ng-upload）。

设置和处理 angularjs 细节相当容易。它还支持进度、取消、拖放，并且是跨浏览器的。

html

<!-- Note: MUST BE PLACED BEFORE angular.js-->
<script src="ng-file-upload-shim.min.js"></script> 
<script src="angular.min.js"></script>
<script src="ng-file-upload.min.js"></script> 

<div ng-controller="MyCtrl">
  <input type="file" ngf-select="onFileSelect($files)" multiple>
</div>

JS：

//inject angular file upload directives and service.
angular.module('myApp', ['ngFileUpload']);

var MyCtrl = [ '$scope', '$upload', function($scope, $upload) {
  $scope.onFileSelect = function($files) {
    //$files: an array of files selected, each file has name, size, and type.
    for (var i = 0; i < $files.length; i++) {
      var file = $files[i];
      $scope.upload = $upload.upload({
        url: 'server/upload/url', //upload.php script, node.js route, or servlet url
        data: {myObj: $scope.myModelObj},
        file: file,
      }).progress(function(evt) {
        console.log('percent: ' + parseInt(100.0 * evt.loaded / evt.total));
      }).then(function(response) {
        var data = response.data;
        // file is uploaded successfully
        console.log(data);
      });
    }
  };
}];

Answer 3

在我的情况下，上述方法适用于 php，但是当我尝试在 node.js 中使用这些方法上传文件时，我遇到了一些问题。 所以不要使用 $http({..,..,...}) 使用普通的 jquery ajax。

对于选择文件使用这个

<input type="file" name="file" onchange="angular.element(this).scope().uploadFile(this)"/>

在控制器中

$scope.uploadFile = function(element) {   
var data = new FormData();
data.append('file', $(element)[0].files[0]);
jQuery.ajax({
      url: 'brand/upload',
      type:'post',
      data: data,
      contentType: false,
      processData: false,
      success: function(response) {
      console.log(response);
      },
      error: function(jqXHR, textStatus, errorMessage) {
      alert('Error uploading: ' + errorMessage);
      }
 });   
};

Answer 4

        var app = angular.module('plunkr', [])
    app.controller('UploadController', function($scope, fileReader) {
        $scope.imageSrc = "";

        $scope.$on("fileProgress", function(e, progress) {
        $scope.progress = progress.loaded / progress.total;
        });
    });




    app.directive("ngFileSelect", function(fileReader, $timeout) {
        return {
        scope: {
            ngModel: '='
        },
        link: function($scope, el) {
            function getFile(file) {
            fileReader.readAsDataUrl(file, $scope)
                .then(function(result) {
                $timeout(function() {
                    $scope.ngModel = result;
                });
                });
            }

            el.bind("change", function(e) {
            var file = (e.srcElement || e.target).files[0];
            getFile(file);
            });
        }
        };
    });

    app.factory("fileReader", function($q, $log) {
    var onLoad = function(reader, deferred, scope) {
        return function() {
        scope.$apply(function() {
            deferred.resolve(reader.result);
        });
        };
    };

    var onError = function(reader, deferred, scope) {
        return function() {
        scope.$apply(function() {
            deferred.reject(reader.result);
        });
        };
    };

    var onProgress = function(reader, scope) {
        return function(event) {
        scope.$broadcast("fileProgress", {
            total: event.total,
            loaded: event.loaded
        });
        };
    };

    var getReader = function(deferred, scope) {
        var reader = new FileReader();
        reader.onload = onLoad(reader, deferred, scope);
        reader.onerror = onError(reader, deferred, scope);
        reader.onprogress = onProgress(reader, scope);
        return reader;
    };

    var readAsDataURL = function(file, scope) {
        var deferred = $q.defer();

        var reader = getReader(deferred, scope);
        reader.readAsDataURL(file);

        return deferred.promise;
    };

    return {
        readAsDataUrl: readAsDataURL
    };
    });



    *************** CSS ****************

    img{width:200px; height:200px;}

    ************** HTML ****************

    <div ng-app="app">
    <div ng-controller="UploadController ">
        <form>
        <input type="file" ng-file-select="onFileSelect($files)" ng-model="imageSrc">
                <input type="file" ng-file-select="onFileSelect($files)" ng-model="imageSrc2">
        <!--  <input type="file" ng-file-select="onFileSelect($files)" multiple> -->
        </form>

        <img ng-src="{{imageSrc}}" />
    <img ng-src="{{imageSrc2}}" />

    </div>
    </div>