Monday, 25 July 2011

Deleting a file using ASP.NET 2.0 and C# .NET


This tutorial will show you how to delete a file on the disk using ASP.NET 2.0 and C#.NET

The .NET Framework offers a number of types that makes accessing resources on filesystems easy to use.

To delete a simple file on the disk, we will need to first import the System.IO namespace. The System.IO namespace contains the File.Delete() method and FileInfo type that we will use to perform our delete with.

using System.IO

If you're looking for a really good web host, try Server Intellect - we found the setup procedure and control panel, very easy to adapt to and their IT team is awesome!

We'll put our code in the btnSubmit_Click() event.

When the btnSubmit_Click() event fires it first checks to see if the file exists using the FileInfo type. If it exists it runs the File.Delete() method to delete it, otherwise it throws a FileNotFoundException which is caught by one of the catch statements below the try block.

protected void btnSubmit_Click(object sender, EventArgs e)
{
try {
FileInfo TheFile = new FileInfo(MapPath(".") + "\\" + txtFile.Text);
if (TheFile.Exists) {
File.Delete(MapPath(".") + "\\" + txtFile.Text);
}
else {
throw new FileNotFoundException();
}
}

catch (FileNotFoundException ex) {
lblStatus.Text += ex.Message;
}
catch (Exception ex) {
lblStatus.Text += ex.Message;
}

}

If you're ever in the market for some great Windows web hosting, try Server Intellect. We have been very pleased with their services and most importantly, technical support.

We have one textbox, a Submit button, a label, and a checkbox on the front end for user interaction. The front end .aspx page looks something like this:

<table width="600" border="0" align="center" cellpadding="5" cellspacing="1" bgcolor="#cccccc">
<tr>
<td width="100" align="right" bgcolor="#eeeeee" class="header1"> File to Delete:</td>
<td align="center" bgcolor="#FFFFFF">
<asp:TextBox ID="txtFile" runat="server"></asp:TextBox>
<br />
<asp:Button ID="btnSubmit" runat="server" Text="Submit" OnClick="btnSubmit_Click" /><br /> &nbsp;
<asp:label ID="lblStatus" runat="server"></asp:label></td>
</tr>
</table>

We migrated our web sites to Server Intellect over one weekend and the setup was so smooth that we were up and running right away. They assisted us with everything we needed to do for all of our applications. With Server Intellect's help, we were able to avoid any headaches!

The flow for the code behind page is as follows.

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}

protected void btnSubmit_Click(object sender, EventArgs e)
{
try {
FileInfo TheFile = new FileInfo(MapPath(".") + "\\" + txtFile.Text);
if (TheFile.Exists) {
File.Delete(MapPath(".") + "\\" + txtFile.Text);
}
else {
throw new FileNotFoundException();
}
}

catch (FileNotFoundException ex) {
lblStatus.Text += ex.Message;
}
catch (Exception ex) {
lblStatus.Text += ex.Message;
}

}
}

Looking for the VB.NET 2005 Version? Click Here!

Looking for more ASP.NET Tutorials? Click Here!

No comments:

Post a Comment