c#解码base64 - Base-64字符数组或字符串的长度无效

using System;

public class Program
{
    public static void Main()
    {
        string base64String = "SGVsbG8gd29ybGQ="; // 示例Base64字符串

        // 检查Base64字符串长度是否合法
        if (base64String.Length % 4 != 0)
        {
            Console.WriteLine("Base-64字符数组或字符串的长度无效");
            return;
        }

        try
        {
            // 解码Base64字符串
            byte[] bytes = Convert.FromBase64String(base64String);
            string decodedString = System.Text.Encoding.UTF8.GetString(bytes);
            Console.WriteLine(decodedString);
        }
        catch (Exception ex)
        {
            Console.WriteLine("解码失败：" + ex.Message);
        }
    }
}