VB实例源码

Print

Print\通用过程s1中的变量:\End Sub

【例6-13】

Dim a As Integer,b As Integer '声明模块级变量

Private Sub Command1_Click()

A = 100:b = 8 '对模块级变量赋值 Print

Print\调用s1前，模块级变量:\ Call s1 '调用通用过程sub1 Print

Print\调用s1后，模块级变量:\End Sub

Sub s1() '通用过程

A = 55:b = 66 '对模块级变量赋值 Print

Print\通用过程s1对模块级变量赋值:\End Sub 【例6-14】

（4）在窗体Form1的代码窗口的顶部，声明模块级变量a和b，分别用来储存程序运行后单击左右两个命令按钮的次数。代码如下：

Private a As Integer Private b As Integer

（5）编写左边的命令按钮的Command1_Clic事件过程。代码如下： Private Sub Command1_Click() Dim s As String I = I + 1 A = a + 1

S = \单击按钮\次,左按钮\次\ MsgBox s,vbOKOnly,\提示\End Sub

（6）编写右边的命令按钮的Command2_Clic事件过程。代码如下： Private Sub Command2_Click() Dim s As String I = I + 1 B = b + 1

S = \单击按钮\次,右按钮\次\ MsgBox s,vbOKOnly,\提示\End Sub 【例6-15】

Sub change()

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Dim d As Integer '声明动态变量d Static s As Integer '声明静态变量s D = d + 1 S = s + 1

Print \动态变量d = \静态变量s = \End Sub

Private Sub Command1_Click() Dim i As Integer For i = 1 To 3

change '或 Call change Next i End Sub 实训

（3）在Form1的窗体模块的代码窗口的最顶部（通用声明段）声明模块级变量title，用来存储字符串。代码如下：

Private title As String '表明是使用通用过程还是函数

（4）定义Sub通用过程MySub，来进行乘法运算。其中的形参x、y按值传递，形参z按地址传递。代码如下：

Private Sub MySub(ByVal x As Integer,ByVal y As Integer,z As Integer) Z = x * y End Sub

定义函数过程MyFun，来进行加法运算。其中的形参m和n是按值传递的。代码如下： Private Function MyFun(ByVal m As Integer,ByVal n As Integer) As Integer MyFun=m+n End Function

（5）添加窗体的事件过程Form_Load，来做些初始化的工作，将文本框置空。代码如下： Private Sub Form_Load() Text1.Text = \ Text2.Text = \ Text3.Text = \End Sub

分别添加两个单选按钮的Click事件过程，来设置框架Frame1和标签Label的Caption属性。代码如下：

Private Sub Option1_Click()

Frame1.Caption = \乘法积运算\ Label1.Caption = \\End Sub

Private Sub Option2_Click() Frame1.Caption = \加法运算\ Label1.Caption = \End Sub

添加命令按钮的事件过程Command1_Click。其中，关键字static声明的静态变量i和j用来储存运算的次数，关键字Dim声明的过程级局部变量a、b、c用来储存三个文本框里的

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数值。代码如下：

Private Sub Command1_Click() Static i As Integer,j As Integer

Dim a As Integer,b As Integer,c As Integer A = Val(Text1.Text) B = Val(Text2.Text)

If Option1.Value=True Then Title = \用过程运算\ Call MySub(a,b,c) i=i+1

Form1.Caption = \第\次\ Else

Title = \用函数运算\ c=MyFun(a, b) j = j+1

Form1.Caption = \第\次\ End If

Text3.Text = c End Sub 第7章 课前体验

Private Sub Frame1_MouseDown(Button As Integer, Shift As Integer, _ X As Single, Y As Single) Form1.Caption = \测试鼠标事件\ Select Case Button

Case 1 '左键，或用常量Visual BasicLeftButton FrameLeft.BackColor = Visual BasicRed FrameRight.BackColor = Visual BasicWhite

Frame1.ToolTipText = \朋友，您刚才在这按了鼠标左键！\ Case 2 '右键 ，或用常量Visual BasicRightButton FrameRight.BackColor = Visual BasicRed FrameLeft.BackColor = Visual BasicWhite

Frame1.ToolTipText = \朋友，您刚才在这按了鼠标右键！\ End Select End Sub 【例7-1】

Private Sub Form_MouseDown(Button As Integer,Shift As Integer,_ X As Single,Y As Single) Print\您触发了MouseDown事件！\End Sub

Private Sub Form_MouseUp(Button As Integer, Shift As Integer,_ X As Single,Y As Single) Print\您又触发了MouseUp事件！\End Sub

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【例7-2】

Private Sub Form_MouseMove(Button As Integer,Shift As Integer,_ X As Single,Y As Single) If Shift=1 And Button=1Then Cls

Print\鼠标指针当前横坐标X=\ Else Cls

Print\鼠标指针当前纵坐标Y=\ End If End Sub 【例7-3】

1）首先，在窗体模块的顶部声明一个逻辑变量paint，如下： Private paint As Boolean

（2）定义窗体上的按下鼠标按键的事件过程，使得变量paint的值在按鼠标左键时为true。再定义释放鼠标按键的事件过程，使得变量paint的值为false。代码如下：

Private Sub Form_MouseDown(Button As Integer,Shift As Integer,_ X As Single,Y As Single) If Button=1 Then paint=True End If End Sub

Private Sub Form_MouseUp(Button As Integer, Shift As Integer, _ X As Single, Y As Single) paint = False End Sub

（3）定义窗体上的鼠标移动事件过程。

Private Sub Form_MouseMove(Button As Integer, Shift As Integer, _ X As Single, Y As Single)

If paint Then ?paint为true时，程序画出轨迹点 PSet(X,Y) End If End Sub 【例7-4】

（2）定义窗体的Form_load事件过程，使列表框中添加几个选项。代码如下： Private Sub Form_Load() List1.AddItem\ List1.AddItem\ List1.AddItem\ List1.AddItem\End Sub

（3）定义列表框的单击事件过程。 Private Sub List1_Click()

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Form1.MousePointer=List1.ListIndex End Sub 【例7-5】

Private Sub Form_KeyPress(KeyAscii As Integer) If KeyAscii >= 97 And KeyAscii <= 122 Then

Print\小写字母：\，ASCII码：\ End If

If KeyAscii >= 65 And KeyAscii<=90 Then

Print\大写字母：\，ASCII码：\ End If End Sub 【例7-6】

Private Sub Form_KeyDown(KeyCode As Integer,Shift As Integer) Dim color As String color=Chr(KeyCode) Select Case color Case\

Label1.BackColor = Visual BasicWhite Case\

Label1.BackColor=Visual BasicRed Case\

Label1.BackColor=Visual BasicGreen Case \

Label1.BackColor=Visual BasicBlue End Select End Sub 【例7-7】

Private Sub Form_KeyDown(KeyCode As Integer,Shift As Integer) Select Case Shift Case1

Label1.Caption=\你按了【SHIFT】键！\ Case2

Label1.Caption=\你按了【CTRL】键！\ Case4

Label1.Caption=\你按了 【ALT】键！\ Case3

Label1.Caption=\你同时按了SHIFT和【CTRL】键！\ Case5

Label1.Caption=\你同时按了SHIFT和【ALT】键！\ Case6

Label1.Caption=\你同时按了CTRL和【ALT】键！\ Case7

Label1.Caption=\你同时按了SHIFT、CTRL和【ALT】键！\

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