x = InputBox(\ y = InputBox(\ z = InputBox(\
Print \ x y z\ Print \排序前\ \ \ If x < y Then t = x: x = y: y = t If x < z Then t = x: x = z: z = t If y < z Then t = y: y = z: z = t
Print \排序后\ \ \End Sub
Private Sub Command2_Click() Dim x!, y!, z!
x = InputBox(\ y = InputBox(\ z = InputBox(\
Print \ x y z\ Print \排序前\ \ \ If x < y Then t = x: x = y: y = t If y < z Then t = y: y = z: z = t If x < y Then
t = x: x = y: y = t End If End If
Print \排序后\ \End Sub
C．4
Dim a(3) As Integer
Private Sub Command1_Click() Picture1.Cls For i = 0 To 2
a(i) = Int(Rnd * 100 + 200) Picture1.Print a(i) Next i End Sub
Private Sub Command2_Click() Picture2.Cls Dim z As Integer For i = 0 To 1
If a(i) > a(i + 1) Then z = a(i + 1) a(i + 1) = a(i) a(i) = z
\
End If Next i
Picture2.Print a(0) Picture2.Print a(1) Picture2.Print a(2) End Sub
C．5
Private Sub Text2_LostFocus() Dim m%, n%, y% m = Val(Text1) n = Val(Text2)
If n Mod 2 <> 0 Then
MsgBox (\脚数必定为偶数\ Text2 = \
Text2.SetFocus Else
y = n / 2 - m If y < 0 Then
MsgBox (\脚数必须≥2倍的头数，请重新输入\ Text2 = \
Text2.SetFocus Else
x = n / 2 - m Label2 = y Label3 = m - y End If End If End Sub
C．6
Private Sub Command1_Click() Dim a!, b!, c!, x1!, x2!, de! a = Text1 b = Text2 c = Text3
de = b * b - 4 * a * c t = 2 * a
If de = 0 Then
Text4 = Format(-b / t, \ Text5 = Format(-b / t, \ElseIf de > 0 Then
Text4 = Format((-b + Sqr(de)) / t, \ Text5 = Format((-b - Sqr(de)) / t, \
Else
Text4 = Format(-b / t, \ Text5 = Format(-b / t, \End If End Sub
Private Sub Command2_Click() Text1 = \Text2 = \Text3 = \Text4 = \Text5 = \End Sub
C．7
Private Sub Text3_LostFocus() Select Case Trim(Text3) Case \
Text4 = Val(Text1) + Val(Text2) Case \
Text4 = Val(Text1) - Val(Text2) Case \
Text4 = Val(Text1) * Val(Text2) Case \
If Val(Text2) = 0 Then
MsgBox \分母为零，重新输入\ Text2 = \
Text2.SetFocus Else
Text4 = Val(Text1) / Val(Text2) End If End Select End Sub
C．8
Private Sub Text1_LostFocus() Select Case Trim(Text1) Case 1
Text2 = \ Case 2
Text2 = \ Case 3
Text2 = \ Case 4
Text2 = \
Case 5
Text2 = \ Case 6
Text2 = \ Case 7
Text2 = \ Case Is > 7, Is < 1
MsgBox \数字为1~7，重新输入\ Text1 = \
Text1.SetFocus End Select End Sub 或者
Private Sub Text1_LostFocus() If Text1 > 7 Or Text1 < 1 Then
MsgBox \数字为1~7，重新输入\ Text1 = \
Text1.SetFocus Else
Text2 = Choose(Text1, \\End If End Sub
D．1
Private Sub Form_Click() For i = 1 To 9
Print Tab(10 - i); String(2 * i - 1, Trim(Str(i))) Next i End Sub
D．2
Private Sub Form_Click() For i = 1 To 10 Step 1
Print Tab(i); String((20 - 2 * i), Chr(64 + i)) Next i End Sub
D．3
Private Sub Command1_Click() Dim s!, t!, i& s = 1 t = 1
For i = 1 To 100000
t = t + i s = s + 1 / t
If 1 / t < 0.00001 Then Exit For Next i
Print \结构\项\End Sub
D．4
Private Sub Command1_Click() Dim n&, pi#, i&
n = InputBox(\输入n值\pi = 2
For i = 1 To n
pi = pi * (2 * i) / (2 * i - 1) * (2 * i) / (2 * i + 1) Next i
Print \当n=\时，pi=\End Sub
D．5
Private Sub Form_Click() Dim s!, t!, i!, a%, n% a = Int(Rnd * 9 + 1) n = Int(Rnd * 6 + 5) t = 0: s = 0
Print \ For i = 1 To n t = t * 10 + a s = s + t Print t; Next i Print
Print \End Sub
D．6
Private Sub Command1_Click() Dim s As Integer s = 0
For i = 1 To 9 For j = 0 To 9 For k = 0 To 9
s = i * 100 + j * 10 + k
If s = i ^ 3 + j ^ 3 + k ^ 3 Then Print s
VB程序设计教程（第3版）课后实验答案
