public class Accepter
{
    private static readonly byte[] salt_ = Encoding.ASCII.GetBytes("258EAFA5-E914-47DA-95CA-C5AB0DC85B11");


    private static string SHA1(byte[] clearData)
    {
        using System.Security.Cryptography.SHA1 sha1 = System.Security.Cryptography.SHA1.Create();
        return Convert.ToBase64String(sha1.ComputeHash(clearData));
    }


    /// <summary>
    /// 生成Sec-WebSocket-Accept标头
    /// </summary>
    /// <param name="secWebSocketKey">客户端发送的Sec-WebSocket-Key标头</param>
    /// <returns></returns>
    /// <exception cref="Exception"></exception>
    public static string Accept(string secWebSocketKey)
    {
        byte[] clearKey = Encoding.ASCII.GetBytes(secWebSocketKey);

        return SHA1([.. clearKey, .. salt_]);
    }
}

//测试
Console.WriteLine(Accepter.Accept("D6ek6vlDxp9QYDNFz1avWA=="));

//输出
//3n54130uwt5msP8XRJ6RxWjBg1c=