File.Move Does Not Work - File Already Exists

I've got a folder:

c:\test

I'm trying this code:

File.Move(@"c:\test\SomeFile.txt", @"c:\test\Test");

I get exception:

File already exists

The output directory definitely exists and the input file is there.

Solution 1:

What you need is:

if (!File.Exists(@"c:\test\Test\SomeFile.txt")) {
    File.Move(@"c:\test\SomeFile.txt", @"c:\test\Test\SomeFile.txt");
}

or

if (File.Exists(@"c:\test\Test\SomeFile.txt")) {
    File.Delete(@"c:\test\Test\SomeFile.txt");
}
File.Move(@"c:\test\SomeFile.txt", @"c:\test\Test\SomeFile.txt");

This will either:

• If the file doesn't exist at the destination location, successfully move the file, or;
• If the file does exist at the destination location, delete it, then move the file.

Edit: I should clarify my answer, even though it's the most upvoted! The second parameter of File.Move should be the destination file - not a folder. You are specifying the second parameter as the destination folder, not the destination filename - which is what File.Move requires. So, your second parameter should be c:\test\Test\SomeFile.txt.

Solution 2:

You need to move it to another file (rather than a folder), this can also be used to rename.

Move:

File.Move(@"c:\test\SomeFile.txt", @"c:\test\Test\SomeFile.txt");

Rename:

File.Move(@"c:\test\SomeFile.txt", @"c:\test\SomeFile2.txt");

The reason it says "File already exists" in your example, is because C:\test\Test tries to create a file Test without an extension, but cannot do so as a folder already exists with the same name.

Solution 3:

Personally I prefer this method. This will overwrite the file on the destination, removes the source file and also prevent removing the source file when the copy fails.

string source = @"c:\test\SomeFile.txt";
string destination = @"c:\test\test\SomeFile.txt";

try
{
    File.Copy(source, destination, true);
    File.Delete(source);
}
catch
{
    //some error handling
}

Solution 4:

You can do a P/Invoke to MoveFileEx() - pass 11 for flags (MOVEFILE_COPY_ALLOWED | MOVEFILE_REPLACE_EXISTING | MOVEFILE_WRITE_THROUGH)

[return: MarshalAs(UnmanagedType.Bool)]
[DllImport("kernel32.dll", SetLastError=true, CharSet=CharSet.Unicode)]
static extern bool MoveFileEx(string existingFileName, string newFileName, int flags);

Or, you can just call

Microsoft.VisualBasic.FileIO.FileSystem.MoveFile(existingFileName, newFileName, true);

after adding Microsoft.VisualBasic as a reference.