c# - System.Beep 等效

Question

是否有任何类可以通过不同的音调在扬声器中发出声音？System.Beep() 是原始的，我不能以双倍频率发送到那里。

比方说，我想要播放 A 声音或 B# 声音。我希望函数调用像这样:

double d = 425,545;
int duration = 500;
int volume = 0.8;
f(d, duration, volume)
f(ToneClass.A, duration, volume)//or like this

Answer 1

频率的整数部分就足够了。你的耳朵甚至不会注意到小数部分。

int frq = 425;
int duration = 500;

Console.Beep(frq, duration);

您可以从这里看到钢琴键的频率。 https://en.wikipedia.org/wiki/Piano_key_frequencies

一些笔记。

使用枚举而不是整数。还可以使用 Task.Delay(duration).Wait(); 休息。 (休息我的意思是沉默笔记)

您可以使用一些公式来计算钢琴键，然后计算键频率，而不是使用大型枚举或大量硬编码整数。您还应该考虑音符长度。你可以在这里看到它们 https://en.wikipedia.org/wiki/Note_value

这是爱德华·格里格的《山王》片段:D

static int GetPianoKey(string note)
{
    int key = -1;
    switch (note[0])
    {
        case 'A': key = 1; break;
        case 'B': key = 3; break;
        case 'C': key = 4; break;
        case 'D': key = 6; break;
        case 'E': key = 8; break;
        case 'F': key = 9; break;
        case 'G': key = 11; break;
    }
    if (note.Length == 2)
    {
        return key + 12*(note[1] - '0');
    }
    if (note.Length == 3)
    {
        return key + 12*(note[2] - '0') + (note[1] == 'b' ? -1 : 1);
    }
    throw new ApplicationException("Wrong note.");
}

static int GetNoteFrequency(string note)
{
    return (int) (Math.Pow(1.05946309436, GetPianoKey(note) - 49)*440);
}

static int GetTickDuration(int tempo)
{
    return 60000/tempo;
}

private static void Main(string[] args)
{
    int duration = GetTickDuration(120); // 120 bpm. duration for quarter note

    for (int i = 0; i < 2; i++)
    {
        Console.Beep(GetNoteFrequency("A3"), duration / 2); // eighth note ==> duration/2
        Console.Beep(GetNoteFrequency("B3"), duration / 2);
        Console.Beep(GetNoteFrequency("C3"), duration / 2);
        Console.Beep(GetNoteFrequency("D3"), duration / 2);

        Console.Beep(GetNoteFrequency("E3"), duration / 2);
        Console.Beep(GetNoteFrequency("C3"), duration / 2);
        Console.Beep(GetNoteFrequency("E3"), duration / 2);
        Task.Delay(duration/2).Wait(); //  eighth rest ==> duration/2

        Console.Beep(GetNoteFrequency("D#3"), duration / 2);
        Console.Beep(GetNoteFrequency("B3"), duration / 2);
        Console.Beep(GetNoteFrequency("D#3"), duration / 2);
        Task.Delay(duration / 2).Wait();

        Console.Beep(GetNoteFrequency("D3"), duration / 2);
        Console.Beep(GetNoteFrequency("Bb3"), duration / 2);
        Console.Beep(GetNoteFrequency("D3"), duration / 2);
        Task.Delay(duration / 2).Wait();

        Console.Beep(GetNoteFrequency("A3"), duration / 2);
        Console.Beep(GetNoteFrequency("B3"), duration / 2);
        Console.Beep(GetNoteFrequency("C3"), duration / 2);
        Console.Beep(GetNoteFrequency("D3"), duration / 2);

        Console.Beep(GetNoteFrequency("E3"), duration / 2);
        Console.Beep(GetNoteFrequency("C3"), duration / 2);
        Console.Beep(GetNoteFrequency("E3"), duration / 2);
        Console.Beep(GetNoteFrequency("A4"), duration / 2);

        Console.Beep(GetNoteFrequency("G3"), duration / 2);
        Console.Beep(GetNoteFrequency("E3"), duration / 2);
        Console.Beep(GetNoteFrequency("C3"), duration / 2);
        Console.Beep(GetNoteFrequency("E3"), duration / 2);

        Console.Beep(GetNoteFrequency("G3"), duration * 2); // half note ==> duration*2
    }
}