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我正在尝试在午餐时间将一个（非常）粗糙的 MP3 播放器组合在一起，到目前为止，我已经可以播放文件，并且我正在研究一种构建文件名列表以启用随机歌曲的方法，但我想我刚刚遇到了障碍。

有没有办法知道当前播放的 MP3 何时结束？活动之类的？就目前而言，我认为我不能拥有播放列表等，除非这是可能的，因为它在每次播放后都会停止。

我已经在下面附上了整个来源，请随时将其分开并给我您可能有的任何反馈，干杯。

using System;
using System.IO;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace X
{
public partial class Form1 : Form
{
    List<string> Names = new List<string>();
    StreamReader reader = File.OpenText(@"C:\X.txt");
    string line;
    OpenFileDialog ofd = new OpenFileDialog();
    StringBuilder buffer = new StringBuilder(128);
    string CommandString;
    [DllImport("winmm.dll")]
    private static extern long mciSendString(string lpstrCommand, StringBuilder lpstrReturnString, int uReturnLength, int hwndCallback);
    public Form1()
    {
        InitializeComponent();
        while ((line = reader.ReadLine()) != null)
        {
            if (line.Trim() != "")
            {
                Names.Add(line.Trim());
            }
        }
    }

    private void btnplay_Click(object sender, EventArgs e)
    {
        if (ofd.FileName == "")
        {
            if (ofd.ShowDialog() == DialogResult.OK)
            {
                ofd.Filter = "MP3 Files|*.mp3";
                CommandString = "open " + "\"" + ofd.FileName + "\"" + " type MPEGVideo alias Mp3File";
                mciSendString(CommandString, null, 0, 0);
                CommandString = "play Mp3File";
                mciSendString(CommandString, null, 0, 0);
            }
        }

        else
        {
            CommandString = "play Mp3File";
            mciSendString(CommandString, null, 0, 0);
        }
    }

    private void btnpause_Click(object sender, EventArgs e)
    {
        CommandString = "pause mp3file";
        mciSendString(CommandString, null, 0, 0);
    }

    private void btnbrowse_Click(object sender, EventArgs e)
    {
        ofd.Filter = "Mp3 files |*.mp3";
        if (ofd.ShowDialog() == DialogResult.OK)
        {
            txtpath.Text = ofd.FileName;
            CommandString = "close Mp3File";
            mciSendString(CommandString, null, 0, 0);
            CommandString = "open " + "\"" + ofd.FileName + "\"" + " type MPEGVideo alias Mp3File";
            mciSendString(CommandString, null, 0, 0);
        }
    }
}
}
4

1 回答 1

2

当您调用 mcisendstring 打开文件时，您可以从 mcisendstring 命令获取通知，只需发送表单句柄并覆盖表单的 wndproc 方法，然后您可以从 MCI 示例代码中获取通知，如下所示。

 private void btnplay_Click(object sender, EventArgs e)
{
    if (ofd.FileName == "")
    {
        if (ofd.ShowDialog() == DialogResult.OK)
        {
            ofd.Filter = "MP3 Files|*.mp3";
            CommandString = "open " + "\"" + ofd.FileName + "\"" + " type MPEGVideo alias Mp3File";
            mciSendString(CommandString, null, 0, this.Handle.ToInt64());
            CommandString = "play Mp3File";
            mciSendString(CommandString, null, 0, this.Handle.ToInt64());
        }
    }

    else
    {
        CommandString = "play Mp3File";
        mciSendString(CommandString, null, 0, this.Handle.ToInt64());
    }
}

// Declare the nofify constant
public const int MM_MCINOTIFY = 953;

// Override the WndProc function in the form
protected override void WndProc(ref Message m) 
{

    if (m.Msg == MM_MCINOTIFY)
    {
        // The file is done playing, do whatever
    }
    base.WndProc(ref m);
}
于 2010-03-02T16:50:04.660 回答