Verify if file exists or not in C#

Question

I am working on an application. That application should get the resume from the users, so that I need a code to verify whether a file exists or not.

I\'m using ASP.N

Answer 1

You can determine whether a specified file exists using the Exists method of the File class in the System.IO namespace:

bool System.IO.File.Exists(string path)

You can find the documentation here on MSDN.

Example:

using System;
using System.IO;

class Test
{
    public static void Main()
    {
        string resumeFile = @"c:\ResumesArchive\923823.txt";
        string newFile = @"c:\ResumesImport\newResume.txt";
        if (File.Exists(resumeFile))
        {
            File.Copy(resumeFile, newFile);
        }
        else
        {
            Console.WriteLine("Resume file does not exist.");
        }
    }
}

Answer 2

You could use:

System.IO.File.Exists(@"c:\temp\test.txt");

Answer 3

Can't comment yet, but I just wanted to disagree/clarify with erikkallen.

You should not just catch the exception in the situation you've described. If you KNEW that the file should be there and due to some exceptional case, it wasn't, then it would be acceptable to just attempt to access the file and catch any exception that occurs.

In this case, however, you are receiving input from a user and have little reason to believe that the file exists. Here you should always use File.Exists().

I know it is cliché, but you should only use Exceptions for an exceptional event, not as part as the normal flow of your application. It is expensive and makes code more difficult to read/follow.

Answer 4

To test whether a file exists in .NET, you can use

System.IO.File.Exists (String)

Answer 5

I have written this code in vb and its is working fine to check weather a file is exists or not for fileupload control. try it

FOR VB CODE ============

    If FileUpload1.HasFile = True Then
        Dim FileExtension As String = System.IO.Path.GetExtension(FileUpload1.FileName)

        If FileExtension.ToLower <> ".jpg" Then
            lblMessage.ForeColor = System.Drawing.Color.Red
            lblMessage.Text = "Please select .jpg image file to upload"
        Else
            Dim FileSize As Integer = FileUpload1.PostedFile.ContentLength

            If FileSize > 1048576 Then
                lblMessage.ForeColor = System.Drawing.Color.Red
                lblMessage.Text = "File size (1MB) exceeded"
            Else
                Dim FileName As String = System.IO.Path.GetFileName(FileUpload1.FileName)

                Dim ServerFileName As String = Server.MapPath("~/Images/Folder1/" + FileName)

                If System.IO.File.Exists(ServerFileName) = False Then
                    FileUpload1.SaveAs(Server.MapPath("~/Images/Folder1/") + FileUpload1.FileName)
                    lblMessage.ForeColor = System.Drawing.Color.Green
                    lblMessage.Text = "File : " + FileUpload1.FileName + " uploaded successfully"
                Else
                    lblMessage.ForeColor = System.Drawing.Color.Red
                    lblMessage.Text = "File : " + FileName.ToString() + " already exsist"
                End If
            End If
        End If
    Else
        lblMessage.ForeColor = System.Drawing.Color.Red
        lblMessage.Text = "Please select a file to upload"
    End If

FOR C# CODE ======================

if (FileUpload1.HasFile == true) {
    string FileExtension = System.IO.Path.GetExtension(FileUpload1.FileName);

    if (FileExtension.ToLower != ".jpg") {
        lblMessage.ForeColor = System.Drawing.Color.Red;
        lblMessage.Text = "Please select .jpg image file to upload";
    } else {
        int FileSize = FileUpload1.PostedFile.ContentLength;

        if (FileSize > 1048576) {
            lblMessage.ForeColor = System.Drawing.Color.Red;
            lblMessage.Text = "File size (1MB) exceeded";
        } else {
            string FileName = System.IO.Path.GetFileName(FileUpload1.FileName);

            string ServerFileName = Server.MapPath("~/Images/Folder1/" + FileName);

            if (System.IO.File.Exists(ServerFileName) == false) {
                FileUpload1.SaveAs(Server.MapPath("~/Images/Folder1/") + FileUpload1.FileName);
                lblMessage.ForeColor = System.Drawing.Color.Green;
                lblMessage.Text = "File : " + FileUpload1.FileName + " uploaded successfully";
            } else {
                lblMessage.ForeColor = System.Drawing.Color.Red;
                lblMessage.Text = "File : " + FileName.ToString() + " already exsist";
            }
        }
    }
} else {
    lblMessage.ForeColor = System.Drawing.Color.Red;
    lblMessage.Text = "Please select a file to upload";
}

Answer 6

Try this:

     string fileName = "6d294041-34d1-4c66-a04c-261a6d9aee17.jpeg";

     string deletePath= "/images/uploads/";

     if (!string.IsNullOrEmpty(fileName ))
        {
            // Append the name of the file to previous image.
            deletePath += fileName ;

            if (File.Exists(HttpContext.Current.Server.MapPath(deletePath)))
            {
                // deletevprevious image
                File.Delete(HttpContext.Current.Server.MapPath(deletePath));
            }
        }