《VB程序设计》课堂例题总结(7)

Private Sub Command1_Click() Dim i%

For i = 0 To List1.ListCount - 1

If List1.List(i) = Combo1.Text Then

MsgBox \你已经点过了\ Exit Sub End If Next

List1.AddItem Combo1.Text End Sub

Private Sub Command2_Click() Dim i%, t As Boolean t = True

For i = 0 To List1.ListCount - 1

If List1.List(i) = Combo2.Text Then t = False

MsgBox \你已经点过了\ Exit For End If Next

If t = True Then List1.AddItem Combo2.Text End Sub

Private Sub Command3_Click() Dim i%

For i = List1.ListCount - 1 To 0 Step -1

If List1.Selected(i) = True Then List1.RemoveItem i Next End Sub

Private Sub Command4_Click() List1.Clear End Sub

Private Sub Form_Load()

Combo1.AddItem \宫爆鸡丁\Combo1.AddItem \青菜蘑菇\Combo1.AddItem \清蒸鲈鱼\Combo1.AddItem \清蒸排骨\Combo1.AddItem \红烧牛肉\

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Combo1.AddItem \清蒸螃蟹\Combo1.AddItem \鱼香肉丝\Combo1.AddItem \芋头扣肉\Combo2.AddItem \奶茶\Combo2.AddItem \牛奶\Combo2.AddItem \豆浆\Combo2.AddItem \可乐\Combo2.AddItem \雪碧\Combo2.AddItem \芬达\Combo2.AddItem \啤酒\Combo2.AddItem \红酒\End Sub

调色板

Rem 注意VB中RGB函数表示颜色的用法，

Rem 以及滚动条的Change事件与Scroll事件的不同之处。

Dim R%, G%, B% '注意变量说明语句的位置，因为在几个过程中均用到这三个变量， '所以要在“通用”“声明”中说明是全局变量 Private Sub Form_Load()

Label5.Caption = \End Sub

Private Sub HScroll1_Scroll() R = HScroll1.Value Label2.Caption = R

Label1.BackColor = RGB(R, G, B)

Label5.Caption = \End Sub

Private Sub HScroll2_Change() G = HScroll2.Value Label3.Caption = G

Label1.BackColor = RGB(R, G, B)

Label5.Caption = \End Sub

Private Sub HScroll3_Change() B = HScroll3.Value Label4.Caption = B

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Label1.BackColor = RGB(R, G, B)

Label5.Caption = \End Sub

在窗体的Label中动态显示系统时间。（即每隔1秒显示一次系统时间）

（Interval = 1000每隔1秒触发1次Timer事件）

Private Sub Form_Load() Label1.Caption = Time() End Sub

Private Sub Timer1_Timer() Label1.Caption = Time() End Sub

倒计时

Dim t As Integer, mm As Integer, ss As Integer, max!, min! Private Sub Command1_Click()

t = InputBox(\请以秒为单位输入倒计时时间\ mm = t \\ 60 ss = t Mod 60

Label1.Caption = mm & \分\秒\ ProgressBar1.max = t ProgressBar1.min = 0 ProgressBar1.Value = t End Sub

Private Sub Command2_Click() Timer1.Enabled = True End Sub

Private Sub Form_Load() Timer1.Enabled = False End Sub

Privite Sub Timer1_Timer() t = t - 1 mm = t \\ 60 ss = t Mod 60

ProgressBar1.Value = t

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Label1.Caption = mm & \分\秒\ If t = 0 Then

Timer1.Enabled = False Label1.Caption = \时间到!\ End If End Sub

移动控件位置的两种代码

对象.Left = x； 对象.Top = y Label1.Left=Label1.Left + 50 Label1.Top=Label1.Top + 50

或用Move方法：对象.Move x, y Label1.Move Label1.Left - 50

Label1.Move Label1.Left, Label1.Top + 50

窗体有一个矩形和一个圆，还有一水平滚动条和一垂直滚动条。程序运行时，移动某个滚动条的滑块，可使圆作相应方向的移动。滚动条刻度值的范围是圆可以在矩形中移动的范围。

Private Sub Form_Load()

Vscroll1.Max = Shape1.Top + Shape1.Height - Shape2.Height Vscroll1.Min = Shape1.Top Hscroll1.Min = Shape1.Left

Hscroll1.Max = Shape1.Left + Shape1.Width - Shape2.Width End Sub

Private Sub Hscroll1_Change() Shape2.Left = Hscroll1.Value End Sub

Private Sub Vscroll1_Change() Shape2.Top = Vscroll1.Value End Sub

小球运动。小球在窗体上任意运动，超出任意边界都能自动弹回来。 Dim h%, w%

Private Sub Form_Load() h = 10 w = 15 End Sub

Private Sub Timer1_Timer()

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Shape1.Left = Shape1.Left + w Shape1.Top = Shape1.Top + h

If Shape1.Left <= 0 Or Shape1.Left + Shape1.Width >= Width Then w = -w End If

If Shape1.Top <= 0 Or Shape1.Top + Shape1.Height >= Height Then h = -h End If End Sub

根据文本框中所输入的数据，滚动条向对应方向移动相应刻度，要求：超过最大刻度或最小刻度则给出相应提示信息

Private Sub Command1_Click()

If HScroll1.Value + Text1.Text > HScroll1.Max Then MsgBox \输入数据太大\

ElseIf HScroll1.Value + Text1.Text < HScroll1.Min Then MsgBox \输入数据太小\Else

HScroll1.Value = HScroll1.Value + Text1.Text End If End Sub

m求组合数 n

Public Function JC#(k%) Dim i% JC = 1 For i = 1 to k JC = JC * i Next

End Function

Private Sub Command1_Click() Dim n%, m%, i%, s1#, s2#, s3# n = Val(InputBox(\输入N\ m = Val(InputBox(\输入M\S1=JC(n) S2=JC(m) S3=JC(n-m)

Print n; \选\有\种组合！\

n!c?m!(n?m)! 35