. Private Sub Command1_Click ( ) Dim a(1To 10)As Integer,i As Integer,s As Integer For i=1To 10 a(i)=2*i Next i Text1.Text=Str(a(10)) s=0 For i=1To 5 s=s+a(i) Next i Text2.Text=Str(s) End Sub.
17.統計1900年~2028年之間的閏年數,在文本框Text1中顯示閏年總數,在列表框List1中顯示所有年份(能被4整除但不能被100整除,或者能被400整除的年份是閏年). 相應的Visual Basic程序如下,在橫線處,填入合適的語句或表達式,把程序補充完整. Private Sub Command1_Click ( ) Dim i As Integer,n As Integer n=0 For i=1900 To 2028 If Leap(i)=1 Then
List1.AddItem
Next i Text1.Text=Str(n) End Sub Function Leap(y As Integer) As Integer'若y為閏年,函數返回值為1,否則為0
If (y Mod 4=0)And (y Mod 100<>0)Then Leap=1 If y Mod 400=0Then Leap=1 End Function.