private static void Rename_File(string FileFullPath, string NewName) // nes name without directory actualy you can simply rename with fileinfo.MoveTo(Fullpathwithnameandextension);
        {
            FileInfo fileInfo = new FileInfo(FileFullPath);
            string DirectoryRoot = Directory.GetParent(FileFullPath).FullName;

            string filecreator = FileFullPath.Substring(DirectoryRoot.Length,FileFullPath.Length-DirectoryRoot.Length);
             
            filecreator = DirectoryRoot + NewName;
            try
            {
                fileInfo.MoveTo(filecreator);
            }
            catch(Exception ex)
            {
                Console.WriteLine(filecreator);
                Console.WriteLine(ex.Message);
                Console.ReadKey();
            }

    enter code here
            // string FileDirectory = Directory.GetDirectoryRoot()

        }

看一下System.IO.File。移动，“移动”文件到一个新名称。

System.IO.File.Move("oldfilename", "newfilename");

在文件中。方法，这将不会覆盖文件，如果它已经存在。它会抛出一个异常。

所以我们需要检查文件是否存在。

/* Delete the file if exists, else no exception thrown. */

File.Delete(newFileName); // Delete the existing file if exists
File.Move(oldFileName,newFileName); // Rename the oldFileName into newFileName

或者用try catch将其包围以避免异常。

Move是做同样的=复制和删除旧的。

File.Move(@"C:\ScanPDF\Test.pdf", @"C:\BackupPDF\" + string.Format("backup-{0:yyyy-MM-dd_HH:mm:ss}.pdf", DateTime.Now));

System.IO.File.Move(oldNameFullPath, newNameFullPath);

public static class ImageRename
{
    public static void ApplyChanges(string fileUrl,
                                    string temporaryImageName,
                                    string permanentImageName)
    {
        var currentFileName = Path.Combine(fileUrl,
                                           temporaryImageName);

        if (!File.Exists(currentFileName))
            throw new FileNotFoundException();

        var extention = Path.GetExtension(temporaryImageName);
        var newFileName = Path.Combine(fileUrl,
                                       $"{permanentImageName}
                                         {extention}");

        if (File.Exists(newFileName))
            File.Delete(newFileName);

        File.Move(currentFileName, newFileName);
    }
}