If file exist in the folder and in the database, how can I add extension at the end of the filename?

For example, if a filename like this exists:

JOHN_DENVER_SMITH.pdf

the code should rename the 2nd record to JOHN_DENVER_SMITH_(1).pdf.

Here's my code:

FileInfo fileInfo = new FileInfo(oldPath);

if (fileInfo.Exists)
{
    try
    {
        if (!Directory.Exists(newPath))
        {
            Directory.CreateDirectory(newPath);
        }

        fileInfo.MoveTo(string.Format("{0}{1}{2}", newPath, firstname.Text   "_"   midlename.Text   "_"   lastname.Text, fileInfo.Extension));
        dataGridView1.Rows.RemoveAt(dataGridView1.SelectedRows[0].Index);
    }
}

CodePudding user response：

Validate if the file already exists on the new location. If it does, add a counter value at the end of your file name and try again. Repeat until the filename doesn't exist.

FileInfo fileInfo = new FileInfo(oldPath);

if (fileInfo.Exists)
{
    try
    {
        if (!Directory.Exists(newPath))
        {
            Directory.CreateDirectory(newPath);
        }
        
        var newFileName = string.Format("{0}{1}{2}", newPath, firstname.Text   "_"   midlename.Text   "_"   lastname.Text, fileInfo.Extension);
        var i = 0;
        while (File.Exists(newFileName))
        {
            newFileName = string.Format("{0}{1}_({2}){3}", newPath, firstname.Text   "_"   midlename.Text   "_"   lastname.Text,   i, fileInfo.Extension);
        }

        fileInfo.MoveTo(newFileName);
        dataGridView1.Rows.RemoveAt(dataGridView1.SelectedRows[0].Index);
    }
}

CodePudding user response：

Try this:

static string GetFilePath(string path)
{
  // do nothing if file not exists
  if(!File.Exists(path)) return path;
  
  int index = path.LastIndexOf(".");
  var ext = index == -1 ? String.Empty : path.SubString(index);
  var pathNoExt = index == -1 ? path : path.SubString(0, index);
  
  int i = 0;
  string result = null;
  
  // Loop until the file does not exist
  while(File.Exists(result = $"{pathNoExt}({  i}){ext}"));
  return path;
}

Usage:

fileInfo.MoveTo(GetFilePath($"{newPath}{firstname.Text}_{midlename.Text}_{lastname.Text}{fileInfo.Extension}"));
        

You can replace string with ReadOnlySpan<char> and SubString with Slice for better performance.

CodePudding user response：

You can write a code to generate the new path like this.

private string NewPathFor(string oldPath)
{
     var fileInfo = new FileInfo(oldPath);
     var newPath = oldPath;
     for (var i = 0; !fileInfo.Exists; i  )
     {
         newPath = $"{Path.GetFileNameWithoutExtension(fileInfo.Name)}_({i}).{fileInfo.Extension}";
         fileInfo = new FileInfo(newPath);
     }
     return newPath;
}

And then call it,

  var oldPath=$"{firstname.Text}_{midlename.Text}_{lastname.Text}.pdf";
  fileInfo.MoveTo(NewPathFor(oldPath));
  dataGridView1.Rows.RemoveAt(dataGridView1.SelectedRows[0].Index);

CodePudding user response：

If Not (IO.File.Exists(fileName & "(" & fileNumber.ToString & ")" & fileExtension) Then 'The file does not exist, do something.. Exit Do Else 'The file does exist, so increment and try the next one...