图7
9．编写电子钟程序，如图8所示。单击“开始”按钮，电子表开始走时；单击“停止”按钮，电子表停止。程序一开始运行，电子表框为空。
图8
10．请利用循环嵌套编写程序,在窗体上输出如图9所示的图案。
图9
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VB程序设计练习题参考答案
一、填空题
1．视图 工具箱 2．Style 3、Selstart 4．Locked
5．Tabindex 0
6．整型 长整型 单精度型 双精度型 7．(x mod 10)*10+x\\10 8．x mod 5 =0 or x mod 9=0 9．False 10．-4 3 11．CDEF 12．33 13．15 14．value
15．Alignment 16．Style 17．enabled 18．0
19．listcount-1 20．clear
21．下拉式列表框
22．窗体模块、标准模块、类模块 23．15000
24．time 或 time$
25．Alt & 下划线 26．连字符“－”
27．KeyPress、 KeyDown、 KeyUp
28．MouseMove、MouseDown和MouseUp
二、选择题
1.A 2.C 3.B 4.C 5.A 6.C 7.B 8.D 9.A 10.D 11.B 12.D 13.B 14.A 15.B 16.D 17.B 18.B 19.C 20.A 21.D 22.B 23.A 24.D 25.B 26.B 27.C 28.B 29.C 30.B 31.A 32.C 33.C 34.A 35.D 36.A 37.B 38.D 39.C 40.D 41.A 42.C 43.A 44.D 45.A 46.D 47.D 48.B 51.B 52.B 53.C 54.A 55.D 56.D 57.C 61.D 62.C 63.A 64.C 65.B 66.B 67.C 71.D 72.D 73.D 74.D 75.D 76.B
三、程序填空
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49.C 50.B 59.D 58.B 60.C 68.A 69.B 70.D 1．RND X Mod 5
2．19 step 3 nFactor(i) sum As Double 1 temp*i 3．min=b c>max
4.list1.additem i list1.listcount-1 list1.list(i) 5．Fontsize Fontname 6．1 100 b/i 7．f3=f1+f2 i>20 8．m=n r=m Mod n
9．Inputbox a(i)>a(j)
10．Isprimer(i+2) str(i) n Mod i tag=false Isprimer=tag
四、编写程序
1．Private Sub Command1_Click() Text1.Text = \ Text2.Text = \ Text3.Text = \
End Sub
Private Sub Command2_Click() Unload Me
End Sub
Private Sub Text1_Change() Text2.Text = Text1.Text Text2.FontSize = 12 Text3.Text = Text1.Text Text3.FontSize = 18
End Sub
2．Private Sub Option1_Click()
Form1.BackColor = RGB(255, 0, 0)
End Sub
Private Sub Option2_Click()
Form1.BackColor = RGB(0, 0, 255)
End Sub
3．Private Sub Option1_Click(Index As Integer) Select Case Index Case 0
Text1.FontSize = 15 Case 1
Text1.FontSize = 20 Case 2
Text1.FontSize = 25 End Select
End Sub
Private Sub Command1_Click() Unload Me
End Sub
4．Private Sub Form_Load() List1.AddItem \北京\ List1.AddItem \上海\
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List1.AddItem \天津\ List1.AddItem \重庆\ List1.AddItem \广东省\ List1.AddItem \河南省\ List1.AddItem \辽宁省\ List1.AddItem \陕西省\
End Sub
Private Sub List1_Click() i = 0
Do While i < List1.ListCount
If List1.Selected(i) = True Then List2.AddItem List1.List(i) List1.RemoveItem i Else
i = i + 1 End If Loop End Sub
5．Private Sub Command1_Click() List1.Clear
For n = 1 To 200
If n Mod 6 = 0 Then List1.AddItem n Next n
End Sub
Private Sub Command2_Click() Unload Me
End Sub
6．Private Sub Command1_Click() Dim char As String, i As Integer i = 0
char = InputBox(\请从键盘输入一个字符\ Do While char <> \ i = i + 1
char = InputBox(\请从键盘输入一个字符\ Loop
Text1.Text = i
End Sub
7．Private Sub Command1_Click()
Dim radius As Single, area As Single, perimeter As Single Const pi = 3.14159
radius = Val(Text1.Text) area = pi * radius * radius perimeter = 2 * pi * radius Text2.Text = area
Text3.Text = perimeter
End Sub
8．Private Sub Command1_Click()
Dim n As Integer
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Dim sum As Integer n = Val(Text1.Text) If n < 50 Then sum = n * 3 Else
sum = n * 2 End If
Text2.Text = sum End Sub
Private Sub Command2_Click() Unload Me End Sub
9．Private Sub Command1_Click()
Timer1.Enabled = True End Sub
Private Sub Command2_Click()
Timer1.Enabled = False End Sub
Private Sub Form_Load()
Text1.Text = \End Sub
Private Sub Timer1_Timer()
Text1.Text = Time End Sub
10．Private Sub Command1_Click() Cls Print
For i = 7 To 2 Step -1 Print Tab(20 - i); For j = 1 To 2 * i- 1 Print \ Next j Print Next i
End Sub
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