A.Private SubText1_KeyPress(KeyAscii As Integer) If KeyAscii<65 or KeyAscii>90 Then MsgBox“请输入大写字母” KeyAscii=0 End If End Sub B. Private Sub Text1_KeyDown( KeyCode As Integer,Shift As Integer) If KeyCode < 65 or KeyCode > 90 Then Msgbox“请输入大写字母” KeyCode = 0 End If End Sub C. Private SuB Text1_MouseDown( Button AS Integer,_ Shift As lnteger,X As Single,Y As Single) If Asc ( Text1. Text) < 65 or Asc ( Text1.Text) > 90 Then Msgbox“请输入大写字母” End If End Sub D. Private Sub Text1_Change( ) If Asc(Text1.Text) >64 And Asc(Text1.Text) >9l Then Msgbox“请输入大写字母” End lf End Sub