How do I check if a given string is a legal/valid file name under Windows?

Question

I want to include a batch file rename functionality in my application. A user can type a destination filename pattern and (after replacing some wildcards in the pattern) I n

Answer 1

This check

static bool IsValidFileName(string name)
{
    return
        !string.IsNullOrWhiteSpace(name) &&
        name.IndexOfAny(Path.GetInvalidFileNameChars()) < 0 &&
        !Path.GetFullPath(name).StartsWith(@"\\.\");
}

filters out names with invalid chars (<>:"/\|?* and ASCII 0-31), as well as reserved DOS devices (CON, NUL, COMx). It allows leading spaces and all-dot-names, consistent with Path.GetFullPath. (Creating file with leading spaces succeeds on my system).

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Used .NET Framework 4.7.1, tested on Windows 7.