前言
前面一系列我们纯粹是讲AngularJS，在讲一门知识时我们应该结合之前所学综合起来来做一个小的例子，前面我们讲了在MVC中上传文件的例子，在本节我们讲讲如何利用AngularJS在WebAPi中如何上传，来巩固下WebAPi并结合AngularJS中对应的一些组件学习下。
AngularJS Upload Files for WebAPi
（一）在WebAPi中我们如何获得上传本地文件的物理路径呢？需要实现此类： MultipartFormDataStreamProvider ，从该类中获取上传文件的物理路径并返回。如下：
public class UploadMultipartFormProvider : MultipartFormDataStreamProvider { public UploadMultipartFormProvider(string rootPath) : base(rootPath) { } public override string GetLocalFileName(HttpContentHeaders headers) { if (headers != null && headers.ContentDisposition != null) { return headers .ContentDisposition .FileName.TrimEnd('"').TrimStart('"'); } return base.GetLocalFileName(headers); } }
（二）为避免有些浏览器不支持多个文件上传我们通过实现 ActionFilterAttribute 特性来加以判断，如下：
public class MimeMultipart : ActionFilterAttribute { public override void OnActionExecuting(HttpActionContext actionContext) { if (!actionContext.Request.Content.IsMimeMultipartContent()) { throw new HttpResponseException( new HttpResponseMessage( HttpStatusCode.UnsupportedMediaType) ); } } public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext) { } }
以上两个类为我们在WebAPi中上传提供一个保障。接下来我们需要的是如何利用AngularJS来上传。
在AngularJS中上传需要用到 ng-file-upload 组件，而非 angularFileUpload 组件，在此之前一直是利用angularFileUpload组件，但是后来逐步迁移并且命名为ng-file-upload组件。同时为了一些加载效果如在github中顶部有加载线的过程，决定也在这里实现一下看看【说明：上传过程用到angular-loading-bar（加载）和ng-file-upload（上传）组件】。
脚本
（1）为了重用，我们将加载组件进行封装。
//common.load.js
(function () { 'use strict'; angular .module('common.load', [ 'angular-loading-bar', 'ngAnimate' ]); })();
（2）启动加载线。
//loadBarCtrl.js
(function (app) { "use strict"; app.controller("loadCtrl", loadCtrl); function loadCtrl(cfpLoadingBar) { cfpLoadingBar.start(); } })(angular.module("common.load"));
（3）上传文件代码
//fileUploadCtrl.js
(function (app) { 'use strict'; app.controller('fileUploadCtrl', fileUploadCtrl); fileUploadCtrl.$inject = ['$scope', '$http', '$timeout', 'Upload']; function fileUploadCtrl($scope, $http, $timeout, Upload, cfpLoadingBar) { $scope.upload = []; $scope.UploadedFiles = []; $scope.startUploading = function ($files) { for (var i = 0; i < $files.length; i++) { var $file = $files[i]; (function (index) { $scope.upload[index] = Upload.upload({ url: "/api/upload", method: "POST", file: $file, withCredentials: false }).progress(function (evt) { }).success(function (data, status, headers, config) { $scope.UploadedFiles.push({ FileName: data.FileName, FilePath: data.LocalFilePath, FileLength: data.FileLength }); cfpLoadingBar.complete(); }).error(function (data, status, headers, config) { }); })(i); } } } })(angular.module("common.load"));
（4）加载主模块以及依赖模块。
//app.js
(function () { 'use strict'; angular .module('angularUploadApp', [ 'ngRoute', 'ngFileUpload', 'common.load' ]) .config(config) config.$inject = ['$routeProvider']; function config($routeProvider) { $routeProvider .when('/', { templateUrl: '../../app/templates/fileUpload.html', controller: 'fileUploadCtrl' }) .otherwise({ redirectTo: '/' }); } })();
界面
@{ Layout = null; } <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title></title> <link href="~/Content/bootstrap.min.css" rel="stylesheet" /> <link href="~/Content/loading-bar.min.css" rel="stylesheet" media="all" /> </head> <body ng-app="angularUploadApp" ng-controller="loadCtrl"> <nav class="navbar navbar-default" role="navigation"> <div class="navbar-header"> <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar"> <span class="sr-only">Toggle navigation</span> <span class="icon-bar"></span> <span class="icon-bar"></span> <span class="icon-bar"></span> </button> <a class="navbar-brand" href="http://www.cnblogs.com/createmyself">Angular File WebAPi Upload by <i style="color:#2da12d;font-weight:bolder;">xpy0928</i></a> </div> <div id="navbar" class="navbar-collapse collapse"> </div> </nav> <div class="container"> <div ng-include src="'../../app/templates/fileUpload.html'"></div> </div> <script src="../../Scripts/jquery-1.10.2.min.js"></script> <script src="../../Scripts/angular.min.js"></script> <script src="../../Scripts/angular-animate.min.js"></script> <script src="../../Scripts/angular-route.js"></script> <script src="../../app/plugins/loading-bar.min.js"></script> <script src="../../app/modules/common.load.js"></script> <script src="../../Scripts/ng-file-upload.min.js"></script> <script src="../../app/app.js"></script> <script src="../../app/controllers/loadBarCtrl.js"></script> <script src="../../app/controllers/fileUploadCtrl.js"></script> </body> </html>
模板页：
<div class="row" ng-controller="fileUploadCtrl"> <div class="col-xs-3"> <div> <input type="file" accept="images/*" ngf-pattern="'.png,.jpg,.gif'" ngf-select="startUploading($files)" multiple> </div> </div> <div class="col-xs-9"> <div class="panel-body"> <div class="panel panel-default" ng-repeat="uploadedFile in UploadedFiles track by $index"> <div class="panel-heading"> <strong>{{uploadedFile.FileName}}</strong> </div> <div class="panel-body"> <div class=" media"> <a class="pull-left" href="#"> <img class="media-object" width="100" ng-src="../uploadimages/{{uploadedFile.FileName}}" /> </a> <div class="media-body"> <div class="lead" style="font-size:14px;color: crimson;500px;word-wrap:break-word">{{uploadedFile.FilePath}}</div> </div> </div> </div> <div class="panel-footer"> 图片总字节： <span style="color:black">{{uploadedFile.FileLength}}</span> </div> </div> </div> </div> </div>
后台api服务:
[RoutePrefix("api/upload")] public class FileUploadController : ApiController { [Route("")] [MimeMultipart] public async Task<FileUploadResult> Post() { var uploadPath = HttpRuntime.AppDomainAppPath + "UploadImages"; if (!Directory.Exists(uploadPath)) Directory.CreateDirectory(uploadPath); var multipartFormDataStreamProvider = new UploadMultipartFormProvider(uploadPath); await Request.Content.ReadAsMultipartAsync(multipartFormDataStreamProvider); string _localFileName = multipartFormDataStreamProvider .FileData.Select(multiPartData => multiPartData.LocalFileName).FirstOrDefault(); return new FileUploadResult { LocalFilePath = _localFileName, FileName = Path.GetFileName(_localFileName), FileLength = new FileInfo(_localFileName).Length }; } }
首先我们来看看例子搭建的结构：
生成界面效果：
下面我们来演示下最终效果：
总结
（1）在WebAPi中用到路由特性时，若在控制器中如 [RoutePrefix("api/upload")] 此时在方法中若未有 [Route("")] 此时在上传的url必须显示添加Post如： url: "/api/upload/post" 若添加则不用显示添加方法名。
（2）在angular中加载模板为
<div ng-include src="''"></div> 【注】：src中要加单引号，否则出错 或者 <div ng-include></div>
（3）对于在WebAPi中上传可以参看此链接，更加详细。
WebAPi：https://github.com/stewartm83/angular-fileupload-sample
对于AngularJS组件中的加载和上传还有更多用法，可以参看如下链接：
ng-file-upload:https://github.com/danialfarid/ng-file-upload
angular-loading-bar:https://github.com/chieffancypants/angular-loading-bar