VB实例源码 

Y As Single)

unload me

End Sub

【例9-1】

Private Sub Command1_Click()

Dim I As Integer For I = 0 To 5

Shape1(I).Shape = I ‘将控件数组中第I个控件的形状属性改

为I

Next End Sub

Private Sub Command2_Click()

Dim I As Integer For I = 0 To 5

Shape1(I).BackStyle = 1 ‘将控件的背景类型更改为“覆盖” Shape1(I).BackColor = QBColor(I) ‘更改控件的背景颜色 Next End Sub

Private Sub Command3_Click()

Dim I As Integer For I = 0 To 5

Shape1(I).FillColor = RGB(255, 255, 255) ‘将控件的填充颜色改为白

色

Shape1(I).FillStyle = I + 2 ‘更改控件的填充方式。因其值为0时为覆盖

方式，其值为1时为透明方式，看不出填充效果，故将值设为从2开始。

Next

End Sub

【例9-2】

Private Sub Command1_Click()

Line(-2,0)-(10,0) ‘画出X轴 Line(0,3)-(0,-3) ‘画出Y轴 For i = 0 To 6.28 Step 0.001 j = Sin(i)

PSet(i, j) ‘ 画出正弦函数图像 Next i End Sub

Private Sub Form_Load()

Form1.Scale(-2,3)-(10,-3) ‘定义坐标系 End Sub

【例9-3】

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Private Sub Form_Click()

Line(500,700)-(2500,700),vbRed Line(1500,100)-(700,2000),vbGreen Line(1500,100)-(2300,2000),vbGreen Line(2500,700)-(700,2000),vbBlue Line(500,700)-(2300,2000),vbBlue End Sub 【例9-4】

Private Sub Form_Click()

Cls

r = Form2.ScaleHeight / 2 ' 圆半径为窗体高度的1/2 x0 = Form2.ScaleWidth / 2 ' 圆的中心坐标（窗体中间） y0 = Form2.ScaleHeight / 2

st = 3.1415926 / 10 ' 将圆等分为 20 份

For i = 0 To 6.283185 Step st ' 用直线将圆周上的这些点两两相连 For j = 0 To i Step st X1 = x0 + r * Cos(i) Y1 = y0 - r * Sin(i) X2 = x0 + r * Cos(j) Y2 = y0 - r * Sin(j) Line (X1, Y1)-(X2, Y2) Next j, i End Sub 【例9-5】

Private Sub Form_Click() Cls

r = Form1.ScaleHeight/4 ‘ 圆半径为窗体高度的1/4 x0 = Form1.ScaleWidth/2 ‘ 圆的中心坐标（窗体中间） y0 = Form1.ScaleHeight/2

st = 3.1415926/25 ‘ 将圆等分为 50 份

For i = 0 To 6.283185 Step st ‘ 以每一个等分点为圆心画圆 x = x0 + r * Cos(i) y = y0 - r * Sin(i) Circle(x, y),r * 0.8 Next i End Sub 【例9-6】

Private Sub Form_Click() Dim numm As Integer Picture1.AutoSize = True ‘图片框大小与图片大小一致 roww = Int(Form1.Width / Picture1.Width) + 1 ‘计算每行可放置多少个图片

coll = Int(Form1.Height / Picture1.Height) + 1 ‘计算每列可放置多少个图片

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For i = 0 To roww For j = 0 To coll

Form1.PaintPicture Picture1.Picture, i * Picture1.Width, j * Picture1.Height, Picture1.Width, Picture1.Height

‘在窗体的行、列上复制图片 Next j Next i

Picture1.Visible = False End Sub

Private Sub Form_Load()

Picture1.Picture = LoadPicture(\‘在图片框中装入图片 Form1.Caption = \图像平铺\End Sub 【例9-7】

Private Sub Form_Click()

Picture1.Cls End Sub

Private Sub Form_Load()

Picture1.ScaleHeight = 100 '设置比例为100. Picture1.ScaleWidth = 100

Picture1.AutoRedraw = True '打开AutoRedraw Picture1.ForeColor = 0 '设置ForeColor Picture1.FillColor = QBColor(9) '设置FillColor Picture1.FillStyle = 0 '设置FillStyle Picture1.Circle (50, 50), 30 '画一个圆

Picture1.AutoRedraw = False '关闭AutoRedraw End Sub

Private Sub Picture1_Click()

Dim I

Picture1.ForeColor =RGB(Rnd * 255,0,0) '选择随机颜色. For I = 5 To 95 Step 10 '画线. Picture1.Line (I,0)-(I,100) Next I

End Sub 【例9-8】

Private Sub Form_Paint()

Dim HalfX,HalfY '声明变量.

HalfX = ScaleLeft + ScaleWidth/2 '圆半径设置到宽度的一半。

HalfY = ScaleTop + ScaleHeight/2 '圆半径设置到高度的一半。画一个圆。 If HalfX > HalfY Then

Circle (HalfX, HalfY), HalfY

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Else

Circle (HalfX, HalfY), HalfX End If End Sub

Private Sub Form_Resize() Refresh

End Sub 实训

Private Sub Form_Click()

Form1.Scale(-2 * 3.14159,1)-(2 * 3.14159,-1) Form1.Line (-2 * 3.14159,0)-(2 * 3.14159,0) Form1.Line(0,1)-(0,-1)

Form1.CurrentX = 0.2:Form1.CurrentY = -0.1:Print\Form1.CurrentX = -3.2:Form1.CurrentY = -0.1:Print\Form1.CurrentX = 3.3:Form1.CurrentY = -0.1:Print\

Form1.CurrentX = -6.2:Form1.CurrentY = -0.1: Print \Form1.CurrentX = 5.7:Form1.CurrentY = -0.1:Print \Form1.CurrentX = 0.2:Form1.CurrentY = 0.5:Print \Form1.CurrentX = 0.2:Form1.CurrentY = -0.5:Print\For I = -6.282 To 6.282 Step 0.02 Form1.PSet (I, Cos(I)) Next I End Sub

第10章 课前体验

Private Sub Combo1_Click()

File1.Pattern = Combo1.Text ‘对文件类型进行过滤 End Sub

Private Sub Dir1_Change()

File1.Path = Dir1.Path ‘目录列表框与文件列表框同步 End Sub

Private Sub Drive1_Change()

Dir1.Path = Drive1.Drive ‘目录列表框与驱动器列表框同步 End Sub

Private Sub Form_Load()

File1.Pattern = \ ‘程序运行时，默认显示EXE文件End Sub

【例10-1】

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Private Sub Form_Load()

Open \打开输出文件

Print #1,\语句测试\向文件中输出一行数据 Print #1, '向文件中输出一个空行 Print #1,\第一分区\第二分区\分区格式输出数据

Print #1,\你好！\按紧凑、分区两种格式输出数据 Print #1, Spc(2); \前面输出2个空格\函数向文件中写入两个空格 Print #1, Tab(5); \从第5列开始输出\函数指定从第5列开始输出 Print #1, \行1\换行测试 Print #1, \行2\

Close #1 '关闭文件 End Sub 【例10-2】

（1）把文本文件的内容一行一行地读入文本框

Text1.Text = “” ‘将文本框置空 Open“D:\\Myfile.txt” For Input As #1

‘以Input方式打开文件“D:\\Myfile.txt”文件，文件号为1。

Do While Not EOF(1) ‘判断文件是否结束

Line Input #1,InputData ‘一次从文件中读入一行，赋给变量

InputData

Text1.Text = Text1.Text+InputData + vbCrlf

‘将InputData变量的值与文本框值连接

Loop Close #1

（2）把文本文件的内容一个字符一个字符地读入文框 Dim InputData As String Text1.Text = “”

Open “D:\\Myfile.txt” For Input As #1

Do While Not EOF(1) ‘判断文件是否结束

InputData=Input(1,#1) ‘每次读一个字符

Text1.Text=Text1.Text+InputData ‘与文本框内容相连接 Loop Close #1

（3）把文本文件的内容一次性读入文本框（仅限于包含西文字符的文本方件）

Text1.Text = \

Open \

Text1.Text = Input(LOF(1), #1)

‘将整个文件的内容全部读出，在文本框中显示出来。

Close #1 【例10-3】

Private Type Student '用户自定义数据类型

Name As String * 8

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