Visual Basic中与MCI相关的API函数包括哪三个？他们的功能是什么？

mciExecute、mciSendString、mciGetErrorString

Declare Function mciExecute Lib "winmm.dll" Alias "mciExecute" (ByVal lpstrCommand As String) As Long
Declare Function mciSendString Lib "winmm.dll" Alias "mciSendStringA" (ByVal lpstrCommand As String, ByVal lpstrReturnString As String, ByVal uReturnLength As Long, ByVal hwnd Callback As Long) As Long
Declare Function mciGetError String Lib "winmm.dll" Alias "mciGetError String A" (ByVal dwError As Long, ByVal lpstrBuffer As String, ByVal uLength As Long) As Long

mciSendString函数的功能是传送指令字符串给MCI，以实现各种播放功能。
mciExecute的功能和mciSendString一样，不同的是当发生错误时mciExecute会弹出对话框显示错误信息。