《VB程序设计》课堂例题总结(3)

End Sub

将输入的字符串首尾颠倒后输出。 方法一：

Private Sub Command1_Click() Dim i%, s1$, ch$, s2$

s1 = InputBox(\请输入一串字符串：\Print \原始字符串为：\For i = 1 To Len(s1) ch = Mid(s1, i, 1) s2 = ch & s2 Next

Print \倒序后字符串为：\End Sub 方法二：

Private Sub Command2_Click() Dim i%, s1$, ch$, s2$

s1 = InputBox(\请输入一串字符串：\Print \原始字符串为：\For i = Len(s1) To 1 Step -1 ch = Mid(s1, i, 1) s2 = s2 & ch Next

Print \倒序后字符串为：\End Sub 方法三：

Private Sub Command3_Click() Dim i%, n%, s$, ch$

s = InputBox(\请输入一串字符串：\Print \原始字符串为：\n = Len(s)

For i = 1 To n / 2 ch = Mid(s, i, 1)

Mid(s, i, 1) = Mid(s, n - i + 1, 1) Mid(s, n - i + 1, 1) = ch Next

Print \倒序后字符串为：\End Sub

统计其中分别有多少个大写字母、小写字母、数字和其他字符并输出结果 Private Sub Command1_Click() Dim i%, s$, ch$, n1%, n2%, n3%

s = InputBox(\请输入一串字符串：\Print \字符串为：\

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n1 = 0: n2 = 0: n3 = 0 For i = 1 To Len(s) ch = Mid(s, i, 1)

If LCase(ch) >= \ n1 = n1 + 1

ElseIf ch >= \ n2 = n2 + 1 Else

n3 = n3 + 1 End If Next

Print \字母的个数为：\Print \数字的个数为：\Print \其他字符的个数为：\End Sub

输入10个同学考试的等级，如果A计5分，B计4分，以此类推，求这10个同学的平均成绩。

Private Sub Form_Click() Dim i%, sum%, mark$, aver! For i = 1 To 10

mark = InputBox(\请输入成绩\ Print mark,

If i Mod 5 = 0 Then Print Select Case UCase(mark)

Case \ sum = sum + 5 Case \ sum = sum + 4 Case \ sum = sum + 3 Case \ sum = sum + 2 Case \ sum = sum + 1 Case Else: sum = sum + 0 End Select Next

aver = sum / 10

Print \平均为：\End Sub

输出斐波那契级数1、1、2、3、5、8、13……的前30项。此级数项的规律是：前两项的值各为1，从第3项起，每一项是前2项的和。（要求一行输出6项） Private Sub Command1_Click() Dim a#, b#, c#, i% a = 1 '第一项为1 b = 1 '第二项为1

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Print a; b; '打印前两项

For i = 3 To 30 '求剩余的28项

c = a + b '每一项都是前两项之和 Print c; '打印输出

If i Mod 6 = 0 Then Print '一行打印6个即换行 a = b '新的第一项 b = c '新的第二项 Next End Sub

编写程序输出2000年至2500年间的所有闰年，要求每行输出8个 Private Sub Command1_Click() Dim y%, n%

For y = 2000 To 2500

If y Mod 400 = 0 Or y Mod 4 = 0 And y Mod 100 <> 0 Then Print y

If y Mod 8 = 0 Then Print End If Next y End Sub

回文字串：香莲碧水动风凉，水动风凉夏日长。长日夏凉风动水，凉风动水碧莲香。 Private Sub Command1_Click() Dim s$, n%, i%

s = InputBox(\请输入一个整数：\n = Len(s)

For i = 1 To n / 2

If Mid(s, i, 1) <> Mid(s, n - i + 1, 1) Then Print s; \不是回文数！\ Exit For End If Next

If i > n / 2 Then Print s; \是回文数！\End Sub

输入一个正整数，判断该数是否为素数。（素数是指一个数只能被1和其本身整除。） Private Sub Command1_Click() Dim i%, n%, s$

n = Val(InputBox(\请输入一个正整数：\s = n & \是素数\For i = 2 To n - 1

If n Mod i = 0 Then s = n & \不是素数\ Exit For

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End If Next Print s End Sub

随机产生10个100～200之间的数，找出其中的最大值。 Private Sub Command1_Click() Dim i%, a%, max% Cls

Randomize

a = Int(Rnd * 101) + 100 '先产生一个数,作为最大值的初值 max = a Print a

For i = 2 To 10 '紧跟着产生剩下的9个数 a = Int(Rnd * 101) + 100 Print a

If a > max Then max = a

'拿新产生的数来与最大值作比较，若比最大值大，则取代其，作为新的最大值 Next

Print \最大值为\End Sub

计算1！+2！+3！+...+10! 的值 Dim sum#, i%, j%, n# sum = 0: n = 1 For i = 1 To 10 n = 1

For j = 1 To i n = n * j Next j

sum = sum + n Next i

Print \！+2！+3！+...+10!=\

显示九九乘法表

Private Sub Form_Click() Dim i%, j% Cls

Print \ |\For i = 1 To 9 Print \Next Print

Print \

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For i = 1 To 9 Print i; \ For j = 1 To i Print i * j; Next j Print Next i End Sub

打印如下图图案

Private Sub Form_Click() Dim i%, j% Cls

For i = 1 To 9

Print Space(11 - i); For j = 1 To 2 * i - 1 Print \ Next j Print Next i

For i = 8 To 1 Step -1

Print Space(11 - i); String(2 * i - 1, \Next End Sub

输出100以内的素数 Private Sub Form_Click() Dim i%, n%,Tag as Boolean For n= 1 to 100 Tag= True For i = 2 To n - 1

If n Mod i = 0 Then Tag=False Exit For End If Next i

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