how to upload excel with duplicate name

Question

how to upload excel file with duplicate name file but its don't do overwrite the previous name file. So if i upload the file with same name it will saving like windows do.

ex. firstly i upload excel file = "fileExcel". then i upload again with same name ="fileExcel". And it should be 2 file on the upload folder, first with name "fileExcel" and "fileExcel(1)".

so if i upload again and again with the same name of file it will continuously grow. (1),(2),(3),(4), etc

here is my code :

    Dim fileName As String = Path.GetFileName(FileUpload1.PostedFile.FileName)
        Dim fileExtension As String = Path.GetExtension(FileUpload1.PostedFile.FileName)
        Dim fileLocation As String = Server.MapPath("~/Upload/" & fileName)
        FileUpload1.SaveAs(fileLocation)
 If fileExtension = ".xls" Then
            connectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & fileLocation & ";Extended Properties=""Excel 8.0;HDR=Yes;IMEX=2"""
        ElseIf fileExtension = ".xlsx" Then
            connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & fileLocation & ";Extended Properties=""Excel 12.0;HDR=Yes;IMEX=2"""
        End If

thanks before

Answer 1

You could use a File.Exists and a counter variable:

Dim fileExtension = IO.Path.GetExtension(fileLocation)
Dim fileName = IO.Path.GetFileNameWithoutExtension(fileLocation)
Dim folder = IO.Path.GetDirectoryName(fileLocation)
Dim counter = 0
While IO.File.Exists(fileLocation)
    counter += 1
    Dim newFileName = String.Format("{0}({1}){2}", fileName, counter, fileExtension)
    fileLocation = IO.Path.Combine(folder, newFileName)
End While

Answer 2

Do not save the uploaded files under the same name as the user provided. You will get many users uploading duplicated names. Generate a new name for each uploaded file and keep the original name in a database and keep a pointer to the generated file in the database. If a file is requested, do a lookup in the database to find the original file.

Answer 3

use File.Exist or use linq to get the file count and change fileName to reflect the new name.

Answer 4

Below code should do it.

public string CalculateNextFileName(string filename, string dir)
{
   var file = Path.GetFileNameWithoutExtension(filename);
   var files = new DirectoryInfo(@"M:\testdir").GetFiles(file + "*");
   return string.Format("{0} ({1})",file, files.Count ());
}

Usage:

var newFileName = "New Text Document.txt";

var nextFileName = CalculateNextFileName(newFileName, "C:\testdir");

This is a very naive implementation that doesn't take account of missing files in the sequence (ie. if files 2 and 3 were missing, this would pump out the name of a potentially existing file).