AngularJS简单文件下载导致路由器重定向

Question 1

HTML：

<a href="mysite.com/uploads/asd4a4d5a.pdf" download="foo.pdf">

当数据库中保留真实姓名时，上传将获得唯一的文件名。我想实现一个简单的文件下载。但是由于以下原因，上面的代码重定向到/：

$routeProvider.otherwise({
    redirectTo: '/', 
    controller: MainController
});

我尝试过

$scope.download = function(resource){
    window.open(resource);
}

但这只是在新窗口中打开文件。

有什么想法如何为任何文件类型启用真正的下载吗？

Question 2

https://docs.angularjs.org/guide/$location#html-link-rewriting

在以下情况下，链接不会被重写；而是，浏览器将执行整页重新加载到原始链接。

包含目标元素的链接示例：
<a href="https://stackoverflow.com/ext/link?a=b" target="_self">link</a>

转到其他域的绝对链接示例：
<a href="http://angularjs.org/">link</a>

以'/'开头的链接在定义base时导致不同的基本路径示例：
<a href="https://stackoverflow.com/not-my-base/link">link</a>

因此，在您的情况下，应添加目标属性，例如...

<a target="_self" href="example.com/uploads/asd4a4d5a.pdf" download="foo.pdf">

Question 3

我们还必须开发一种解决方案，甚至可以与需要身份验证的API配合使用（请参阅本文）

概括地说，使用AngularJS的方法如下：

步骤1：建立专用指令

// jQuery needed, uses Bootstrap classes, adjust the path of templateUrl
app.directive('pdfDownload', function() {
return {
    restrict: 'E',
    templateUrl: '/path/to/pdfDownload.tpl.html',
    scope: true,
    link: function(scope, element, attr) {
        var anchor = element.children()[0];

        // When the download starts, disable the link
        scope.$on('download-start', function() {
            $(anchor).attr('disabled', 'disabled');
        });

        // When the download finishes, attach the data to the link. Enable the link and change its appearance.
        scope.$on('downloaded', function(event, data) {
            $(anchor).attr({
                href: 'data:application/pdf;base64,' + data,
                download: attr.filename
            })
                .removeAttr('disabled')
                .text('Save')
                .removeClass('btn-primary')
                .addClass('btn-success');

            // Also overwrite the download pdf function to do nothing.
            scope.downloadPdf = function() {
            };
        });
    },
    controller: ['$scope', '$attrs', '$http', function($scope, $attrs, $http) {
        $scope.downloadPdf = function() {
            $scope.$emit('download-start');
            $http.get($attrs.url).then(function(response) {
                $scope.$emit('downloaded', response.data);
            });
        };
    }] 
});

步骤2：建立范本

<a href="" class="btn btn-primary" ng-click="downloadPdf()">Download</a>

步骤3：使用

<pdf-download url="/some/path/to/a.pdf" filename="my-awesome-pdf"></pdf-download>

这将呈现一个蓝色按钮。单击后，将下载PDF（警告：后端必须以Base64编码提供PDF！）并放入href中。该按钮变为绿色，并将文本切换为“保存”。用户可以再次单击，然后将看到my-awesome.pdf文件的标准下载文件对话框。

我们的示例使用的是PDF文件，但显然，只要编码正确，您就可以提供任何二进制格式。

Question 4

如果您需要更高级的指令，我建议您使用在Internet Explorer 11，Chrome和FireFox上正确测试的解决方案。

希望对您有所帮助。

HTML：

<a href="#" class="btn btn-default" file-name="'fileName.extension'"  ng-click="getFile()" file-download="myBlobObject"><i class="fa fa-file-excel-o"></i></a>

指令：

directive('fileDownload',function(){
    return{
        restrict:'A',
        scope:{
            fileDownload:'=',
            fileName:'=',
        },

        link:function(scope,elem,atrs){


            scope.$watch('fileDownload',function(newValue, oldValue){

                if(newValue!=undefined && newValue!=null){
                    console.debug('Downloading a new file'); 
                    var isFirefox = typeof InstallTrigger !== 'undefined';
                    var isSafari = Object.prototype.toString.call(window.HTMLElement).indexOf('Constructor') > 0;
                    var isIE = /*@cc_on!@*/false || !!document.documentMode;
                    var isEdge = !isIE && !!window.StyleMedia;
                    var isChrome = !!window.chrome && !!window.chrome.webstore;
                    var isOpera = (!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;
                    var isBlink = (isChrome || isOpera) && !!window.CSS;

                    if(isFirefox || isIE || isChrome){
                        if(isChrome){
                            console.log('Manage Google Chrome download');
                            var url = window.URL || window.webkitURL;
                            var fileURL = url.createObjectURL(scope.fileDownload);
                            var downloadLink = angular.element('<a></a>');//create a new  <a> tag element
                            downloadLink.attr('href',fileURL);
                            downloadLink.attr('download',scope.fileName);
                            downloadLink.attr('target','_self');
                            downloadLink[0].click();//call click function
                            url.revokeObjectURL(fileURL);//revoke the object from URL
                        }
                        if(isIE){
                            console.log('Manage IE download>10');
                            window.navigator.msSaveOrOpenBlob(scope.fileDownload,scope.fileName); 
                        }
                        if(isFirefox){
                            console.log('Manage Mozilla Firefox download');
                            var url = window.URL || window.webkitURL;
                            var fileURL = url.createObjectURL(scope.fileDownload);
                            var a=elem[0];//recover the <a> tag from directive
                            a.href=fileURL;
                            a.download=scope.fileName;
                            a.target='_self';
                            a.click();//we call click function
                        }


                    }else{
                        alert('SORRY YOUR BROWSER IS NOT COMPATIBLE');
                    }
                }
            });

        }
    }
})

在控制器中：

$scope.myBlobObject=undefined;
$scope.getFile=function(){
        console.log('download started, you can show a wating animation');
        serviceAsPromise.getStream({param1:'data1',param1:'data2', ...})
        .then(function(data){//is important that the data was returned as Aray Buffer
                console.log('Stream download complete, stop animation!');
                $scope.myBlobObject=new Blob([data],{ type:'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'});
        },function(fail){
                console.log('Download Error, stop animation and show error message');
                                    $scope.myBlobObject=[];
                                });
                            };

服务中：

function getStream(params){
                 console.log("RUNNING");
                 var deferred = $q.defer();

                 $http({
                     url:'../downloadURL/',
                     method:"PUT",//you can use also GET or POST
                     data:params,
                     headers:{'Content-type': 'application/json'},
                     responseType : 'arraybuffer',//THIS IS IMPORTANT
                    })
                    .success(function (data) {
                        console.debug("SUCCESS");
                        deferred.resolve(data);
                    }).error(function (data) {
                         console.error("ERROR");
                         deferred.reject(data);
                    });

                 return deferred.promise;
                };

BACKEND（在SPRING上）：

@RequestMapping(value = "/downloadURL/", method = RequestMethod.PUT)
public void downloadExcel(HttpServletResponse response,
        @RequestBody Map<String,String> spParams
        ) throws IOException {
        OutputStream outStream=null;
outStream = response.getOutputStream();//is important manage the exceptions here
ObjectThatWritesOnOutputStream myWriter= new ObjectThatWritesOnOutputStream();// note that this object doesn exist on JAVA,
ObjectThatWritesOnOutputStream.write(outStream);//you can configure more things here
outStream.flush();
return;
}

Question 5

在模板中

<md-button class="md-fab md-mini md-warn md-ink-ripple" ng-click="export()" aria-label="Export">
<md-icon class="material-icons" alt="Export" title="Export" aria-label="Export">
    system_update_alt
</md-icon></md-button>

在控制器中

     $scope.export = function(){ $window.location.href = $scope.export; };