《VisualBasic程序设计教程第2版》课后部分编程题参考答案.pdf

1 第第 1 章章 1. 按要求设置窗体属性 2在窗体上建立一个标签 Label1。程序代码如下： Private Sub Form_Click() Label1.Caption = “你单击了窗体“ End Sub Private Sub Form_DblClick() Label1.Caption = “你双击了窗体“ End Sub 3 在窗体上建立两个文本框 Text1(输入数)、Text2(输出数)和一个命令按钮 Command1。两个文本框的 Text 属性均为空。 Private Sub Command1_Click() Dim x As Single x = Val(Text1.Text) Text2.Text = 15 * x End Sub 第第 2 章章 13 题：按要求完成操作练习。 4 Private Sub Command1_Click()“最大化“按钮 Form1.WindowState = 2最大化 End Sub Private Sub Command2_Click()“还原“按钮 Form1.WindowState = 0还原 End Sub Private Sub Command3_Click()“最小化“按钮 Form1.WindowState = 1最小化 End Sub 5在窗体上建立三个文本框 Text1(第一个数)、Text2(第二个数)、Text3(计算结果)和一个命令按 钮 Command1(“计算”)。 Private Sub Command1_Click() Dim x As Single Dim y As Single x = Val(Text1.Text) y = Val(Text2.Text) Text3.Text = x * x + y * y End Sub 6. 在窗体上建立两个文本框 Text1(输入一串字符)、Text2(输出结果)和一个命令按钮 Command1。 Private Sub Command1_Click() Dim x As String x = Left(Text1.Text, 1) + Right(Text1.Text, 1) Text2.Text = x End Sub 第第 3 章章 1在窗体上建立一个文本框 Text1(输入 n 值)、三个标签 Label1(第一个随机数)、Label2(第二个随机 数)和 Label3(第三个随机数)，以及一个命令按钮 Command1。 Private Sub Command1_Click() n = Val(Text1.Text) Randomize x = Int(1 + n * Rnd) Label1.Caption = “第一个随机数“ + Str(x) x = Int(1 + n * Rnd) Label2.Caption = “第二个随机数“ + Str(x) x = Int(1 + n * Rnd) Label3.Caption = “第三个随机数“ + Str(x) End Sub 2在窗体上建立了四个文本框 Text1、Text2、Text3 和 Text4，以及一个命令按钮 Command1(“交换” ) 和 Command2(“合并”)。 2 Private Sub Command1_Click()“交换” t = Text1.Text Text1.Text = Text2.Text Text2.Text = Text3.Text Text3.Text = t End Sub Private Sub Command2_Click()“合并” t = Text1.Text + Text2.Text + Text3.Text Text4.Text = t End Sub 3. (1) Rnd * 9000 + 1000(2) Str(x)(3) Mid(s, 3, 1) + Mid(s, 2, 1) + Left(s, 1) 4.Private Sub Command1_Click()往左 Text1.Left = 0 End Sub Private Sub Command2_Click()往右 Text1.Left = Form1.Width - Text1.Width End Sub Private Sub Command3_Click()居中 Text1.Left = (Form1.Width - Text1.Width) / 2 End Sub 5. Private Sub Cmd1_Click() Lab1.Visible = True Lab1.Caption = “您已下达显示命令“ End Sub Private Sub Form_Click() Cmd1.Visible = True End Sub 6. Private Sub Form_KeyPress(KeyAscii As Integer) Show Print “输入字符：“; Chr(KeyAscii), “ASCII 码为;“; KeyAscii End Sub Private Sub Form_DblClick() Cls End Sub 7. 产生这三个消息框的相应语句是： 产生第 1 个消息框：x = MsgBox(“在这里显示提示信息“, 4 + 0, “请确认“) 产生第 2 个消息框：x = MsgBox(“在这里显示“ + Chr(13) + “提示信息“,3 + 0,“请确认“) 产生第 3 个消息框：x = MsgBox(“在这里显示“+Chr(13)+“提示信息“,2 + 16 + 0,“请确认“) 第第 4 章章 1. 在窗体上建立两个文本框 Text1(输入数)及 Text2(显示结果)， 一个命令按钮 Command1( “判断” )。 Private Sub Command1_Click()“判断” x = Val(Text1.Text) If x Mod 2 = 0 Then Text2.Text = “偶数“ Else 消息 Text2.Text = “奇数“ End If End Sub 2窗体上建立了一个文本框 Text1，用于显示结果。 Private Sub Form_Load() x = Val(InputBox(“请输入星期几(06)“) Select Case x Case Is = 0 Text1.Text = “星期日(Sunday)“ Case Is = 1 Text1.Text = “星期一(Monday)“ Case Is = 2 3 Text1.Text = “星期二(Tuesday)“ Case Is = 3 Text1.Text = “星期三(Wednesday)“ Case Is = 4 Text1.Text = “星期四(Thursday)“ Case Is = 5 Text1.Text = “星期五(Friday)“ Case Is = 6 Text1.Text = “星期六(Saturday)“ Case Else Text1.Text = “输入错误“ End Select End Sub 3窗体上建立了一个文本框 Text1(“输入口令”)和一个命令按钮 Command1(“检查”)。 Private Sub Command1_Click()“检查” x = Text1.Text If x = “12345678“ Then MsgBox (“欢迎你用机!“) Else MsgBox (“对不起，口令错“) End If Text1.Text = “ Text1.SetFocus End Sub Private Sub Form_Load() Text1.Text = “ Text1.MaxLength = 8 Text1.PasswordChar = “*“ End Sub 4窗体上建立了两个文本框 Text1(输入字符串)及 Text2(转换结果)，一个命令按钮 Command1(“清 除”)。 Private Sub Command1_Click()“清除” Text1.Text = “ Text2.Text = “ Text1.SetFocus End Sub Private Sub Text1_KeyPress(KeyAscii As Integer) Dim s As String * 1 s = Chr(KeyAscii) Select Case s Case “A“ To “Z“ s = LCase(s) Case “a“ To “z“ s = UCase(s) Case Else s = “*“ End Select Text2.Text = Text2.Text + s End Sub 5 分别选择”红”、 ”绿”、 ”蓝”复选框后，单击命令按钮 Command1 时，通过 RGB 函数调配的颜 色作为一个标签的背景色（BackColor） 。 Private Sub Command1_Click() r = 0: g = 0: b = 0 If Check1.Value = 1 Then”红”复选框 r = 255 End If If Check2.Value = 1 Then”绿”复选框 g = 255 End If If Check3.Value = 1 Then”蓝”复选框 4 b = 255 End If Label1.BackColor = RGB(r, g, b) End Sub 6程序代码如下： Private Sub Form_Load() LabClk.Caption = “0“ LabClk.Alignment = 1 LabClk.BorderStyle = 1 LabClk.FontSize = 22 LabClk.FontName = “黑体“ TimClk.Interval = 1000 End Sub Private Sub TimClk_Timer() LabClk.Caption = Val(LabClk.Caption) + 1 End Sub 7 (1) Chr(KeyAscii)(2) ElseIf Chr(KeyAscii) (3) CheC = CheC - 1(4) CheC(5) Is 0 或 Else 第第 5 章章 1. 和数为：1.21。程序代码如下： Private Sub Form_Load() Show s = 0 For k = 1 To 100 s = s + 1 / (1 + k * 4) Next k Print s End Sub 2. 程序代码如下： Private Sub Form_Load() Dim i As Integer, a As Integer, b As Integer, c As Integer Show For i = 100 To 999 a = Int(i / 100) b = Int(i - 100 * a) / 10) c = i - 100 * a - 10 * b If a * a * a + b * b * b + c * c * c = i Then Print i End If Next i End Sub 3. 在窗体上建立一个文本框 Text1(初始值)、一个列表框 List1(显示结果)和一个命令按钮 Comd1(“查找”)。 Private Sub Comd1_Click()“查找” Dim n As Integer n = Val(Text1.Text) List1.Clear:k = 0 Do While k = “A“ And t = 0.00001 Print a; “的平方根为“; xn1 End Sub 第第 6 章章 1. 程序代码如下： Private Sub Form_Load() Show Dim a(100) As Single n = Val(InputBox(“输入个数 n“) Print “处理前数据 :“ For k = 1 To n a(k) = Val(InputBox(“请输入第“ Next k Print M = Int(n / 2) For k = 1 To M h = n - k + 1 t = a(h):a(h) = a(k):a(k) = t Next k Print “处理的结果 :“ For k = 1 To n Print a(k); Next k End Sub 2. 程序代码如下： Private Sub Form_Load() Dim a(6, 6) As Integer 6 Show For i = 1 To 6 For j = 1 To 6 Select Case i Case Is j a(i, j) = 2 Case Is = j a(i, j) = 0 End Select Print a(i, j); Next j Print Next i For i = 1 To 6 t = a(1, i):a(1, i) = a(6, i):a(6, i) = t Next i Print: Print For i = 1 To 6 For j = 1 To 6 Print a(i, j); Next j Print Next i End Sub 3在窗体上建立两个列表框 List1(处理前数据)和 List2(处理后数据)，以及标签 Label1。程序代 码如下： Private Sub Form_Load() Dim a(100) As Integer, b(100) As Integer Randomize n = 100 For i = 1 To n输入数组 a 的 n 个元素 x = Int(20 * Rnd) List1.AddItem x a(i) = x Next i k = 0 For i = 1 To n删除零元素 If a(i) y Then m = x Else m = y End If If m “(2) Mid(s, p+1)(3) n 4. 程序代码如下： Private Sub Form_Load() Dim x As Single, n As Integer, y As Double x = InputBox(“x=“, “求 X 的 n 次方“) n = InputBox(“n=“, “求 X 的 n 次方“) y = Power(x, n) Show 8 Print x; “的“; n; “次方=“; Format(y, “#,#.#“) End Sub Function Power(x As Single, n As Integer) As Double If n 1 Then Power = Power(x, n - 1) * x Else Power = x End If End Function 5在窗体上设置三个窗体 Form1Form3。 Form1 中建立了两个文本框 Text1( “用户名” )和 Text2( “密 码”)，以及命令按钮 Command1(“判断”)。Form2 中建立了一个文本框 Text1(其 Text 属性值为“欢迎你 使用本系统”)和命令按钮 Command1(“返回”)。Form3 中建立了一个文本框 Text1(其 Text 属性值为“对 不起，请向管理员查询”)和命令按钮 Command1(“退出”)。 Dim n As Integer Private Sub Command1_Click()窗体 Form1 的“判断” usern = Trim(Text1.Text):passw = Trim(Text2.Text) If usern = “username“ And passw = “password“ Then Form1.Hide Form2.Show Else n = n + 1:Text1.SetFocus If n = 3 Then Form1.Hide Form3.Show End If End If Text1.Text = “:Text2.Text = “ End Sub Private Sub Form_Activate() Text1.Text = “:Text2.Text = “ Text1.SetFocus End Sub Private Sub Command1_Click()窗体 Form2 的“返回” Form2.Hide Form1.Show End Sub Private Sub Command1_Click()窗体 Form3 的“退出” Unload Form1 Unload Form2 Unload Form3 End End Sub 6. (1) Form1 窗体模块程序代码： Private Sub Form_Load() Randomize End Sub Private Sub Command1_Click()“生成随机数“ Dim s As String s = “ For i = 1 To 10 a(i) = Int(11 + 90 * Rnd) s = s + Str(a(i) + “,“ Next i Text1.Text = Left(s, Len(s) - 1) End Sub Private Sub Command2_Click()“求最大数“ Text2.Text = Max() End Sub Private Sub Command3_Click()“打开排序窗口“ Form1.Hide隐藏主窗体 Form2.Show显示“排序”窗体 9 End Sub Private Sub Command4_Click()“结束“ Unload Form1隐藏主窗体 Unload Form2显示“排序”窗体 End End Sub (2) Form2 窗体模块程序代码： Private Sub Command1_Click()“排序” Dim t As String Call Sort(t) Text1.Text = t End Sub Private Sub Command2_Click()“返回” Form2.Hide隐藏“排序”窗体 Form1.Show显示主窗体 End Sub (3) 标准模块程序代码： Public a(1 To 10) As Single Function Max() As Single求最大值 Dim m As Single m = a(1) For i = 2 To 10 If m a(j) Then t = a(i): a(i) = a(j): a(j) = t End If Next j s = s + Str(a(i) + “,“ Next i s = s + Str(a(10) End Sub 第第 8 章章 1. 程序代码如下： Dim d(1 To 20) As Integer Private Sub Command1_Click()“产生随机数“ For i = 1 To 20 d(i) = Int(1 + 99 * Rnd) List1.AddItem d(i) Next i End Sub Private Sub Command2_Click()“保存“ Open “MyFile3.txt“ For Output As #1 For i = 1 To 20 Write #1, d(i) Next i Close #1 End Sub Private Sub Command3_Click()“读出“ Open “MyFile3.txt“ For Input As #1 Do While Not EOF(1) Input #1, x 10 List2.AddItem x Loop Close #1 End Sub Private Sub Command4_Click()“结束“ End End Sub 2 本程序的用户界面和程序代码较为复杂，请见具体程序文件。 第第 9 章章 1. 程序代码如下： Private Sub Form_load() Dim x(3) As Single, y As Single On Error GoTo errln以后出错时转移到 errln y = 2 / 0产生“除数为 0“的错误 x(4) = 1产生“下标越界“的错误 MsgBox (“终止程序的运行“) Unload Me卸载窗体 End errln:标号 Select Case Err.Number Case 11“除数为 0“的错误码为 11 MsgBox (“除数为 0(错误码为 11)，跳过该错误“) Resume Next返回 Case 9“下标越界“的错误码为 9 MsgBox (“下标越界(错误码为 9)，跳过该错误“) Resume Next返回 Case Else其他错误处理 MsgBox (“错误发生在“ For j = 1 To 2 * i - 1 If j 9 Then k = k + 7 Print Chr(k + 48); Next j Next i End Sub 3(1) n = n + 1(2) d(1, j) = d(3, j)(3) d(i, 2) = d(i, 4) (4) i = j(5) d(i, j) = d(i, j) + 1(6) n = 0(7) Text1.Text 第第 10 章章 1在窗体上建立一个水平滚动条 HScroll1 和一个文本框 Text1。程序代码如下： Private Sub Form_Load() HScroll1.Max = 1000 HScroll1.Min = 0 HScroll1.LargeChange = 5 HScroll1.LargeChange = 10 HScroll1.Value = 500 11 End Sub Private Sub HScroll1_Change() Text1.Text = HScroll1.Value End Sub Private Sub HScroll1_Scroll() Text1.Text = HScroll1.Value End Sub 2. 在窗体上建立一个计时器 Timer1 和“开始” 、 “停止”两个命令按钮。程序代码如下： Private len_S As Single, s As Integer模块级变量 Private Sub Command1_Click()“开始” Timer1.Enabl