FileUpload在HTML中是个常用的基础控件，在涉及到上传各种格式的文件时候都会用到；笔者前段时间正好用到它做上传功能，记录下来做一些累积，

前端到后台用的是的Jquery中的Ajax进行数据传输，在后台的逻辑处理中以HttpPostedFileBase的对象调用SaveAs(ServerSavePath)方法去存储到指定路径。

Microsoft在技术文档中是这样描述HttpPostedFileBase的

Serves as the base class for classes that provide access to individual files that have been uploaded by a client. 用于提供客户端上传的单个文件访问的类的基类   接下来看看如何实现：
HTML   <div class="container">

        <div class="row">

            <input type="file" id="files" multiple name="files" /><button class="btn-default" id="UploadButton">点我上传</button>

        </div>

    </div>
JS  $(function () {

            $(‘#UploadButton‘).click(function () {

              var data= new FormData();

                var fileUpload = $("#files").get(0);

                files = fileUpload.files;

                if (files.length > 0) {

                    for (var i = 0; i < files.length; i++) {

                        data.append(files[i].name, files[i]); //FormData 是以键值对的形式模拟表单，然后以
XMLHttpRequest请求出去。表单的
enctype的属性为multipart/form-data 

                    }

                    $.ajax({

                        url: ‘/IENotes/CommonFile,

                        type: "POST", 

                        processData: false,   //  不序列化，直接将data进行传输。

                        contentType: false,    // 告诉jquery不要设置content-Type请求头，设置成true会对FormData的边界造成干扰，接收不到数据。

                        data: data,

                        success: function (result) {

                            //location.href("Index");

                            alert(result);

                        },

                        error: function (err) {

                            alert(err.statusText);

                        }

                    });

                }

            });

        });  
后台

public static bool CommonFile(){

 var  files = Request.Files.AllKeys.Distinct(); //将传输过来的files进行去重
                if (files != null)
                {
                    foreach (string each in files)
                    {
                        HttpPostedFileBase file = Request.Files[each] as HttpPostedFileBase; //注意，这里有一个对象类型转换的过程，需要将传过来的对象转换成HttpPostedFileBase对象
                        if (file != null)
                        {
                            var InputFileName = Path.GetFileName(file.FileName);
                            string str4 = AppDomain.CurrentDomain.BaseDirectory;    //获取基目录，它由程序集冲突解决程序用来探测程序集。

                            var ServerSavePath = Path.Combine(Server.MapPath("~/Uploads/") );
                            if (!Directory.Exists(ServerSavePath))//检查路径是否存在
                            {
                                Directory.CreateDirectory(ServerSavePath);
                            }
                            var SavePath = Path.Combine(ServerSavePath ,InputFileName);

                            file.SaveAs(SavePath);
                        }

                    }
                    return true;
                }
                else
                {
                    return false;
                }

}