Upload large files must first modify the web.config file, or upload error. MaxRequestLength add the following configuration in the web.config file representation can upload a maximum value, the unit is KB, requestLengthDiskThreshold represents a file after exceeding the number of KB cache to the file system, not cached in memory, in order to reduce the burden of memory. requestLengthDiskThreshold must be less than maxRequestLength
<configuration> <system.web> <httpRuntime maxRequestLength ="1048576" requestLengthDiskThreshold ="100"/> </system.web> </configuration>
Upload page
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebFormLargeFile.aspx.cs" Inherits="WebApplication1.WebFormLargeFile" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> <style type ="text/css" > .fileList { margin-bottom :5px; } </style> </head> <body> <form id="form1" runat="server"> <div> <asp:Label ID ="lblFile" runat ="server" AssociatedControlID ="upFile" Text ="World Document："></asp:Label> <asp:FileUpload ID ="upFile" runat ="server" /> <asp:Button ID ="btnAdd" runat ="server" onclick="btnAdd_Click" Text ="上传" /> <hr /> <asp:Repeater ID ="rptFiles" runat ="server" DataSourceID ="srcFiles" > <HeaderTemplate > <ul class ="fileList"> </HeaderTemplate> <ItemTemplate > <li> <asp:HyperLink ID ="lnkFile" runat ="server" Text ='<%#Eval("FileName") %>' NavigateUrl ='<%#Eval("Id","~/FileHandlerLarge.ashx?Id={0}") %>'></asp:HyperLink> </li> </ItemTemplate> <FooterTemplate > </ul> </FooterTemplate> </asp:Repeater> </div> <asp:SqlDataSource ID="srcFiles" runat="server" ConnectionString="Data Source=localhost;Initial Catalog=test;Integrated Security=True" ProviderName ="System.Data.SqlClient" SelectCommand="SELECT * FROM [Files]"></asp:SqlDataSource> </form> </body> </html>
using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.IO; using System.Data.SqlClient; using System.Data; namespace WebApplication1 { public partial class WebFormLargeFile : System.Web.UI.Page { const string connStr = "Data Source=localhost;Initial Catalog=test;Integrated Security=True"; protected void Page_Load(object sender, EventArgs e) { } protected void btnAdd_Click(object sender, EventArgs e) { if (upFile.HasFile) { if (CheckFileType(upFile.FileName)) { AddFile(upFile.FileName, upFile.FileContent); rptFiles.DataBind(); } } } private bool CheckFileType(string fileName) { return Path.GetExtension(fileName).ToLower() == ".doc"; } private void AddFile(string fileName,Stream upload) { using(SqlConnection conn=new SqlConnection(connStr)) { string sql = "insert into Files (FileName) values(@FileName)\n select @Id=SCOPE_IDENTITY() "; SqlCommand cmd = new SqlCommand(sql,conn); cmd.Parameters.AddWithValue("@FileName", fileName); SqlParameter IdParam= new SqlParameter("@Id", SqlDbType.Int); IdParam.Direction = ParameterDirection.Output; cmd.Parameters.Add(IdParam); conn.Open(); cmd.ExecuteNonQuery(); int id =Convert.ToInt32(IdParam.Value); StoreFile(id, conn, upload); } } private void StoreFile(int Id, SqlConnection conn, Stream upload) { int bufferLength = 8040; BinaryReader reader = new BinaryReader(upload);//从流中读取字节数据 byte[] chuk = new byte[bufferLength]; chuk = reader.ReadBytes(bufferLength); SqlCommand cmd =new SqlCommand("update Files set FileBytes=@FileBytes where Id =@id",conn); cmd.Parameters.AddWithValue("@id", Id); cmd.Parameters.Add("@FileBytes", SqlDbType.VarBinary, bufferLength).Value = chuk; the cmd.ExecuteNonQuery (); // SET column name .write (expression, @ offset, @ length) from the start of replacing a column with the value of the index @length length character expression // SET column name .write (expression, null , 0) is added at the end of a column // the SET column name .write (expression, 0, null) from the start position of the replacement // the SET column name .write (null, @ offset, @ length) can be used to delete data // set column names .write (expression, @ offset, @ length) can only be used for SQL Server2005 above // set the column name .write (expression, @ offset, @ length) usage reference HTTPS: // www.debugease.com /mssqlbasic/1274092.html the SqlCommand cmdAppend = new new the SqlCommand ( " Update Files SET FileBytes.Write (@ FileBytes, null, 0) WHERE Id = @ ID " , Conn); cmdAppend.Parameters.AddWithValue ( " @id ", Id); cmdAppend.Parameters.Add("FileBytes", SqlDbType.VarBinary, bufferLength); chuk = reader.ReadBytes(bufferLength); while (chuk.Length > 0) { cmdAppend.Parameters["FileBytes"].Value = chuk; cmdAppend.ExecuteNonQuery(); chuk = reader.ReadBytes(bufferLength); } reader.Close(); } } }
File Handling page
using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Data.SqlClient; using System.Data; namespace WebApplication1 { /// <summary> /// FileHandlerLarge 的摘要说明 /// </summary> public class FileHandlerLarge : IHttpHandler { const string connStr = "Data Source=localhost;Initial Catalog=test;Integrated Security=True"; public void ProcessRequest(HttpContext context) { context.Response.ContentType = "application/msword"; context.Response.Buffer = false; SqlConnection conn = new SqlConnection(connStr); SqlCommand cmd = new SqlCommand("select FileBytes from Files where Id =@Id", conn); cmd.Parameters.AddWithValue("@Id", context.Request["Id"]); using (conn) { conn.Open(); SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.SequentialAccess); if (reader.Read()) { int bufferSize = 8040; byte[] chunk = new byte[bufferSize]; long retCount = 0; long startIndex = 0; //public override long GetBytes(int i, long dataIndex, byte[] buffer, int bufferIndex, int length) // stream of bytes read into the buffer from the specified column offset, and given as an array from the beginning of the buffer offset. = reader.GetBytes retCount ( 0 , startIndex, the chunk, 0 , bufferSize); the while (retCount == bufferSize) { context.Response.BinaryWrite (the chunk); startIndex + = bufferSize; retCount = reader.GetBytes ( 0 , startIndex, the chunk , 0 , bufferSize); } // writes the last byte array byte [] = actualChunk new new byte [retCount - . 1 ]; Buffer.BlockCopy(chunk, 0, actualChunk, 0, (int)retCount - 1); context.Response.BinaryWrite(actualChunk); } } context.Response.Write("Hello World"); } public bool IsReusable { get { return false; } } } }