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()

        }

First solution Avoid System.IO.File.Move solutions posted here (marked answer included). It fails over networks. However, copy/delete pattern works locally and over networks. Follow one of the move solutions, but replace it with Copy instead. Then use File.Delete to delete the original file. You can create a Rename method to simplify it. Ease of use Use the VB assembly in C#. Add reference to Microsoft.VisualBasic Then to rename the file: Microsoft.VisualBasic.FileIO.FileSystem.RenameFile(myfile, newName); Both are strings. Note that myfile has the full path. newName does not. For example: a = "C:\whatever\a.txt"; b = "b.txt"; Microsoft.VisualBasic.FileIO.FileSystem.RenameFile(a, b); The C:\whatever\ folder will now contain b.txt.

Use:

using System.IO;

string oldFilePath = @"C:\OldFile.txt"; // Full path of old file
string newFilePath = @"C:\NewFile.txt"; // Full path of new file

if (File.Exists(newFilePath))
{
    File.Delete(newFilePath);
}
File.Move(oldFilePath, newFilePath);

在我的例子中，我希望重命名文件的名称是唯一的，所以我在名称中添加了一个日期-时间戳。这样，'old'日志的文件名总是唯一的:

if (File.Exists(clogfile))
{
    Int64 fileSizeInBytes = new FileInfo(clogfile).Length;
    if (fileSizeInBytes > 5000000)
    {
        string path = Path.GetFullPath(clogfile);
        string filename = Path.GetFileNameWithoutExtension(clogfile);
        System.IO.File.Move(clogfile, Path.Combine(path, string.Format("{0}{1}.log", filename, DateTime.Now.ToString("yyyyMMdd_HHmmss"))));
    }
}

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);
    }
}

// Source file to be renamed  
string sourceFile = @"C:\Temp\MaheshChand.jpg";  
// Create a FileInfo  
System.IO.FileInfo fi = new System.IO.FileInfo(sourceFile);  
// Check if file is there  
if (fi.Exists)  
{  
// Move file with a new name. Hence renamed.  
fi.MoveTo(@"C:\Temp\Mahesh.jpg");  
Console.WriteLine("File Renamed.");  
}