using System;
using System.IO;

class Program
{
    static void Main()
    {
        // 獲取所有無效的文件名字符
        char[] invalidChars = Path.GetInvalidFileNameChars();

        Console.WriteLine("Invalid file name characters:");
        foreach (char c in invalidChars)
        {
            Console.Write($"- {c} ");
        }
        Console.WriteLine();

        // 示例：檢查一個字符串是否包含禁止的字符
        string fileName = "test:file.txt";
        if (IsFileNameValid(fileName))
        {
            Console.WriteLine("The file name is valid.");
        }
        else
        {
            Console.WriteLine("The file name contains invalid characters.");
        }
    }

    /// <summary>
    /// 檢查文件名是否包含禁止的字符。
    /// </summary>
    /// <param name="fileName">要檢查的文件名。</param>
    /// <returns>如果文件名中不包含任何禁止的字符，則返回 true；否則返回 false。</returns>
    static bool IsFileNameValid(string fileName)
    {
        char[] invalidChars = Path.GetInvalidFileNameChars();
        foreach (char c in invalidChars)
        {
            if (fileName.Contains(c))
            {
                return false;
            }
        }
        return true;
    }
}