Asp.Net 上传大文件

代码

namespace WebUploadFile
{
     public class HttpUploadModule : IHttpModule
    {
         /// <summary>
         /// IHttpModule Dispose
         /// </summary>
         public void Dispose(){}

         /// <summary>
         /// init begin request
         /// </summary>
         /// <param name="application"></param>
         public void Init(HttpApplication application)
        {
            application.BeginRequest += new EventHandler( this .Application_BeginRequest);
        }

         /// <summary>
         /// http request file is contains file upload
         /// </summary>
         /// <param name="sender"></param>
         /// <param name="e"></param>
         private void Application_BeginRequest(Object sender, EventArgs e)
        {
            HttpApplication app = sender as HttpApplication;
            HttpWorkerRequest request = GetWorkerRequest(app.Context);
            Encoding encoding = app.Context.Request.ContentEncoding;

             int bytesRead = 0 ; // 已读数据大小
             int read;            // 当前读取的块的大小
             int count = 8192 ;    // 分块大小
             byte [] buffer;        // 保存所有上传的数据

             if (request != null )
            {
                 // 返回 HTTP 请求正文已被读取的部分。
                 byte [] tempBuff = request.GetPreloadedEntityBody(); // 要上传的文件

                 // 如果是附件上传
                 if (tempBuff != null && IsUploadRequest(app.Request))      // 判断是不是附件上传
                {
                     // 获取上传大小
                     long length = long .Parse(request.GetKnownRequestHeader(HttpWorkerRequest.HeaderContentLength));

                    buffer = new byte [length];
                    count = tempBuff.Length; // 分块大小

                     // 将已上传数据复制过去
                     //
                    Buffer.BlockCopy(tempBuff, // 源数据
                         0 ,                        // 从0开始读
                        buffer,                  // 目标容器
                        bytesRead,                // 指定存储的开始位置
                        count);                  // 要复制的字节数。

                     // 开始记录已上传大小
                    bytesRead = tempBuff.Length;

                     // 循环分块读取，直到所有数据读取结束
                     while (request.IsClientConnected() && ! request.IsEntireEntityBodyIsPreloaded() && bytesRead < length)
                    {
                         // 如果最后一块大小小于分块大小，则重新分块
                         if (bytesRead + count > length)
                        {
                            count = ( int )(length - bytesRead);
                            tempBuff = new byte [count];
                        }

                         // 分块读取
                        read = request.ReadEntityBody(tempBuff, count);

                         // 复制已读数据块
                        Buffer.BlockCopy(tempBuff, 0 , buffer, bytesRead, read);

                         // 记录已上传大小
                        bytesRead += read;

                    }
                     if (request.IsClientConnected() && ! request.IsEntireEntityBodyIsPreloaded())
                    {
                         // 传入已上传完的数据
                        InjectTextParts(request, buffer);
                    }
                }
            }
        }

        HttpWorkerRequest GetWorkerRequest(HttpContext context)
        {

            IServiceProvider provider = (IServiceProvider)HttpContext.Current;
             return (HttpWorkerRequest)provider.GetService( typeof (HttpWorkerRequest));
        }

         /// <summary>
         /// 传入已上传完的数据
         /// </summary>
         /// <param name="request"></param>
         /// <param name="textParts"></param>
         void InjectTextParts(HttpWorkerRequest request, byte [] textParts)
        {
            BindingFlags bindingFlags = BindingFlags.Instance | BindingFlags.NonPublic;

            Type type = request.GetType();

             while ((type != null ) && (type.FullName != " System.Web.Hosting.ISAPIWorkerRequest " ))
            {
                type = type.BaseType;
            }

             if (type != null )
            {
                type.GetField( " _contentAvailLength " , bindingFlags).SetValue(request, textParts.Length);
                type.GetField( " _contentTotalLength " , bindingFlags).SetValue(request, textParts.Length);
                type.GetField( " _preloadedContent " , bindingFlags).SetValue(request, textParts);
                type.GetField( " _preloadedContentRead " , bindingFlags).SetValue(request, true );
            }
        }

         private static bool StringStartsWithAnotherIgnoreCase( string s1, string s2)
        {
             return ( string .Compare(s1, 0 , s2, 0 , s2.Length, true , CultureInfo.InvariantCulture) == 0 );
        }

         /// <summary>
         /// 是否为附件上传
         /// 判断的根据是ContentType中有无multipart/form-data
         /// </summary>
         /// <param name="request"></param>
         /// <returns></returns>
         bool IsUploadRequest(HttpRequest request)
        {
             return StringStartsWithAnotherIgnoreCase(request.ContentType, " multipart/form-data " );
        }
    }
}

代码

< httpModules >
             < add name = " ScriptModule " type = " System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35 " />
             < add name = " HttpUploadModule " type = " WebUploadFile.HttpUploadModule, WebUploadFile " />
         </ httpModules >
         < httpRuntime maxRequestLength = " 2000000 " executionTimeout = " 1300 " />

代码

< form id = " form1 " runat = " server " >
         < div >
             < input id = " firstFile " type = " file " name = " firstFile " runat = " server " />
             < asp:Button ID = " Button1 " runat = " server " OnClick = " Button1_Click " Text = " 上传 " />
             < asp:Label ID = " Label1 " runat = " server " ></ asp:Label >
         </ div >
     </ form >

代码

protected void Button1_Click( object sender, EventArgs e)
        {
             // 要保存的位置
             string strDesPath = " D:\\ " ;
             string strFileName = this .firstFile.PostedFile.FileName;
            strFileName = strDesPath + strFileName.Substring(strFileName.LastIndexOf( " \\ " ));
             //
             this .firstFile.PostedFile.SaveAs(strFileName);
             this .Label1.Text = " 文件保存到了： " + strFileName;
        }

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Asp.Net 上传大文件

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