Tuesday, March 9, 2010

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
To delete a simple file on the disk, we will need to first import the System.IO namespace. 

The System.IOFile.Delete() method and FileInfo type that we will use to perform our delete with.
using System.IO

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;
    }
}
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:

 
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;
      }
}

No comments:

Post a Comment