Rename some files in a folder

Question

I have a task of changing the names of some files (that is, adding id to each name dynamically) in a folder using C#.

Example: help.txt to 1help.txt

How can

Answer 1

On .NET Framework 4.0 I use FileInfo.MoveTo() method that only takes 1 argument

Just to move files my method looks like this

private void Move(string sourceDirName, string destDirName)
{
    DirectoryInfo dir = new DirectoryInfo(sourceDirName);
    FileInfo[] files = null;

    files = dir.GetFiles();

    foreach (FileInfo file in files)
    {
        string temppath = Path.Combine(destDirName, file.Name);
        file.MoveTo(temppath);
    }
}

to rename files my method looks like this

private void Rename(string folderPath)
{
   int fileCount = 0;

   DirectoryInfo dir = new DirectoryInfo(folderPath);

   files = dir.GetFiles();

   foreach (FileInfo file in files)
   {
       fileCount += 1;
       string newFileName = fileCount.ToString() + file.Name;
       string temppath = Path.Combine(folderPath, newFileName);

       file.MoveTo(temppath);
   }
}

AS you can see to Rename file it syntax is almost the same as to Move it, just need to modify the filename before using MoveTo() method.