The asp.net FileUpload control allows a user to browse and upload files to
the web server. From developers perspective, it is as simple as dragging and dropping
the FileUpload control to
the aspx page. An extra control, like a Button control, or some other control is needed, to actually
save the file.
<asp:FileUploadID="FileUpload1"runat="server"/>
<asp:ButtonID="B1"runat="server"Text="
Save"OnClick="B1_Click"/>
By default,
the FileUpload control allows a maximum of 4MB file to be uploaded and
the execution timeout is 110 seconds. These properties can be changed from within
the web.config file’s httpRuntime section.
The maxRequestLength property determines
the maximum file size that can be uploaded.
The executionTimeout property determines
the maximum time for execution.
<httpRuntimemaxRequestLength="8192"executionTimeout="220"/>
From code behind,
the mime type, size of
the file, file name and
the extension of
the file can be obtained.
The maximum file size that can be uploaded can be obtained and modified using
the System.Web.Configuration.HttpRuntimeSection class.
Files can be alternatively saved using
the System.IO.HttpFileCollection class. This collection class can be populated using
the Request.Files property.
The collection contains HttpPostedFile class which contains a reference to
the class.
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.Configuration;
using System.Web.Configuration;
namespace WebApplication1
{
public partial class WebControls : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
//Using FileUpload control to upload and
save files
protected void B1_Click(object sender, EventArgs e)
{
if (FileUpload1.HasFile && FileUpload1.PostedFile.ContentLength >
0)
{
//mime type of
the uploaded file
string mimeType = FileUpload1.PostedFile.ContentType;
//size of
the uploaded file
int size = FileUpload1.PostedFile.ContentLength; // bytes
//extension of
the uploaded file
string extension = System.IO.Path.GetExtension(FileUpload1.FileName);
//save file
string path = Server.MapPath("path");
FileUpload1.SaveAs(path + FileUpload1.FileName);
}
//maximum file size allowed
HttpRuntimeSection rt = new HttpRuntimeSection();
rt.MaxRequestLength = rt.MaxRequestLength * 2;
int length = rt.MaxRequestLength;
//execution timeout
TimeSpan ts = rt.ExecutionTimeout;
double secomds = ts.TotalSeconds;
}
//Using Request.Files to
save files
private void AltSaveFile()
{
HttpFileCollection coll = Request.Files;
for (int i = 0; i < coll.Count; i++)
{
HttpPostedFile file = coll[i];
if (file.ContentLength > 0)
;//do something
}
}
}
}
