VON
宣告
Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As String) As Long
傳送字串用↓
Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Any) As Long
SendMessage與PostMessage不同的地方是SendMessage會直接把訊息丟給視窗，而不把訊息丟給該視窗的執行緒佇列，訊息丟出去，直到該視窗程序有處理該訊息為止。