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SendMessage, SendMessageBynum, SendMessageByString
VB声明Declare Function SendMessage& Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any)Declare Function SendMessageBynum& Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long)Declare Function SendMessageByString& Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As String)说明调用一个窗口的窗口函数，将一条消息发给那个窗口。除非消息处理完毕，否则该函数不会返回。SendMessageBynum， SendMessageByString是该函数的“类型安全”声明形式返回值Long，由具体的消息决定参数表参数类型及说明hwndLong，要接收消息的那个窗口的句柄wMsgLong，消息的标识符wParamLong，具体取决于消息lParamAny，具体取决于消息转载于:https://www.cnblogs.com/kttec/archive/2011/07/08/2100903.html
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