如何从sql数据库下载文件 [英] how to download a file from sql database
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问题描述
这是我的代码，用于在sql服务器中上传文件
this is my code to upload a file in sql server
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="fileupload.aspx.cs" Inherits="fileupload" %>
<!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>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:FileUpload ID="FileUpload1" runat="server" />
<br />
<asp:Button ID="btnUpload" runat="server" Text="Upload"
OnClick="btnUpload_Click" />
<br />
<asp:Label ID="lblMessage" runat="server" Text=""
Font-Names = "Arial"></asp:Label>
<br />
<br />
<asp:GridView ID="GridView1" runat="server" CellPadding="4" ForeColor="#333333"
GridLines="None">
<RowStyle BackColor="#E3EAEB" />
<FooterStyle BackColor="#1C5E55" Font-Bold="True" ForeColor="White" />
<PagerStyle BackColor="#666666" ForeColor="White" HorizontalAlign="Center" />
<SelectedRowStyle BackColor="#C5BBAF" Font-Bold="True" ForeColor="#333333" />
<HeaderStyle BackColor="#1C5E55" Font-Bold="True" ForeColor="White" />
<EditRowStyle BackColor="#7C6F57" />
<AlternatingRowStyle BackColor="White" />
</asp:GridView>
</div>
</form>
</body>
</html>
(.cs)后面的代码
code behind(.cs)
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;
using System.IO;
public partial class fileupload : System.Web.UI.Page
{
SqlConnection con = new SqlConnection("Data Source=GRAFT11;Initial Catalog=sample;Integrated Security=True;");
protected void Page_Load(object sender, EventArgs e)
{
con.Open();
DataSet ds = new DataSet();
SqlDataAdapter da = new SqlDataAdapter("select * from fileupload", con);
da.Fill(ds);
GridView1.DataSource = ds;
GridView1.DataBind();
con.Close();
}
protected void btnUpload_Click(object sender, EventArgs e)
{
// Read the file and convert it to Byte Array
string filePath = FileUpload1.PostedFile.FileName;
string filename = Path.GetFileName(filePath);
string ext = Path.GetExtension(filename);
string contenttype = String.Empty;
//Set the contenttype based on File Extension
switch (ext)
{
case ".doc":
contenttype = "application/vnd.ms-word";
break;
case ".docx":
contenttype = "application/vnd.ms-word";
break;
case ".xls":
contenttype = "application/vnd.ms-excel";
break;
case ".xlsx":
contenttype = "application/vnd.ms-excel";
break;
case ".jpg":
contenttype = "image/jpg";
break;
case ".png":
contenttype = "image/png";
break;
case ".gif":
contenttype = "image/gif";
break;
case ".pdf":
contenttype = "application/pdf";
break;
}
if (contenttype != String.Empty)
{
Stream fs = FileUpload1.PostedFile.InputStream;
BinaryReader br = new BinaryReader(fs);
Byte[] bytes = br.ReadBytes((Int32)fs.Length);
//insert the file into database
string strQuery = "insert into fileupload(Name, ContentType, Data)" +
" values (@Name, @ContentType, @Data)";
SqlCommand cmd = new SqlCommand(strQuery);
cmd.Parameters.Add("@Name", SqlDbType.VarChar).Value = filename;
cmd.Parameters.Add("@ContentType", SqlDbType.VarChar).Value
= contenttype;
cmd.Parameters.Add("@Data", SqlDbType.Binary).Value = bytes;
InsertUpdateData(cmd);
lblMessage.ForeColor = System.Drawing.Color.Green;
lblMessage.Text = "File Uploaded Successfully";
}
else
{
lblMessage.ForeColor = System.Drawing.Color.Red;
lblMessage.Text = "File format not recognised." +
" Upload Image/Word/PDF/Excel formats";
}
}
private Boolean InsertUpdateData(SqlCommand cmd)
{
cmd.CommandType = CommandType.Text;
cmd.Connection = con;
try
{
con.Open();
cmd.ExecuteNonQuery();
return true;
}
catch (Exception ex)
{
Response.Write(ex.Message);
return false;
}
finally
{
con.Close();
con.Dispose();
}
}
}
我想要一个代码从sql数据库下载上传文件......
请帮助我.......
i want a code to download the upload file from sql database.........
please help me.......
推荐答案
检查本文
在ASP中使用SQL Server上载和下载文件. NET [ ^ ]
Check this article
Upload and Download Files with SQL Server in ASP.NET[^]
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