asp.net use HttpWorkerRequest to upload large files

Front Page

<form id= "Form1" runat= "Server" enctype= "Multipart/form-data" method= "POST" >
<div>
<input id= "Firstfile" type= "file" Name= "Firstfile" runat= "Server" ><br/>
&nbsp;<asp:button id= "Button1" runat= "Server" onclick= "button1_click" text= "Upload"/><br/>
<asp:label id= "Label1" runat= "Server" ></asp:Label></div>
</form>

Background page

protected void Page_Load (object sender, EventArgs e)
{

}

protected void Button1_Click (object sender, EventArgs e)
{
The location to save
String Strdespath = "d:\\";
String strFileName = This.firstFile.PostedFile.FileName;
strFileName =strdespath + strFileName;
//
This.firstFile.PostedFile.SaveAs (strFileName);
This. Label1.Text = "File saved to:" + strFileName;
}

Configuration file

<add name= "Httpuploadmodule" type= "Httpmodelapp.httpuploadmodule, Httpmodelapp"/>

Class

Using System;
Using System.Collections;
Using System.Collections.Specialized;
Using System.Globalization;
Using System.IO;
Using System.Text;
Using System.Web;

Using System.Reflection;

Namespace Httpmodelapp
{
Implement IHttpModule interface
public class Httpuploadmodule:ihttpmodule
{
Public Httpuploadmodule ()
{

}

public void Init (HttpApplication application)
{
Subscribe to Events
Application. BeginRequest + = new EventHandler (this. Application_BeginRequest);
}

public void Dispose ()
{
}

        private void Application_BeginRequest (Object sender, EventArgs e)
& nbsp;       {
             HttpApplication app = sender as HttpApplication;
            HttpWorkerRequest request = Getworkerrequest (app. context);
            Encoding Encoding = App. Context.Request.ContentEncoding;

int bytesread = 0; Read Data size
int read; The size of the block currently being read
int count = 8192; Chunking size
byte[] buffer; Save all uploaded data

if (Request!= null)
{
Returns the portion of the HTTP request body that has been read.
byte[] Tempbuff = Request. Getpreloadedentitybody (); Files to upload

If the attachment is uploaded
if (tempbuff!= null && isuploadrequest (APP). Request)//To determine if attachment upload
{
Get upload Size
//
Long length = long. Parse (Request. Getknownrequestheader (httpworkerrequest.headercontentlength));

Buffer = new Byte[length];
Count = Tempbuff.length; Chunking size

Copy uploaded data to the past
//
Buffer.blockcopy (Tempbuff,//source data
0,//starting from 0 read
Buffer,//target container
Bytesread,//Specify the start location of the store
count); The number of bytes to replicate.

Start recording uploaded size
Bytesread = Tempbuff.length;

Loop-block read until all data reads end
while (request. IsClientConnected () &&!request. isentireentitybodyispreloaded () && bytesread < length)
{
If the last piece size is less than the block size, the block is split again
if (Bytesread + count > Length)
{
Count = (int) (length-bytesread);
Tempbuff = new Byte[count];
}

Chunk Read
Read = Request. Readentitybody (Tempbuff, Count);

Copy a read block of data
Buffer.blockcopy (tempbuff, 0, buffer, bytesread, read);

Record already uploaded size
Bytesread + = read;

}
if (request). IsClientConnected () &&!request. Isentireentitybodyispreloaded ())
{
Passing in data that has been uploaded
Injecttextparts (request, buffer);
}
}
}
}

HttpWorkerRequest Getworkerrequest (HttpContext context)
{

IServiceProvider Provider = (IServiceProvider) httpcontext.current;
Return (HttpWorkerRequest) provider. GetService (typeof (HttpWorkerRequest));
}

<summary>
Passing in data that has been uploaded
</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>
Whether to upload an attachment
The basis of judgment is whether there are any multipart/form-data in contenttype
</summary>
<param name= "Request" ></param>
<returns></returns>
BOOL Isuploadrequest (HttpRequest request)
{
return Stringstartswithanotherignorecase (Request. ContentType, "Multipart/form-data");
}
}
}

Note: You need to add a reference HttpModelApp.dll