VB中常见的错误1、运行下面的 Visual Basic程序，单击命令按钮 Command1，出现如下图所示的提示信息：Private Sub Command1_Click()Dim a As Single, b As Singlea = Val(Text1.Text)b = 10If a >= bb = a * a + 2 * bEnd IfLabel1.Caption = Str(b)End Sub出现该错误的原因是A．If语句缺少Then B．If语句缺少ElseC．变量a的数据类型说明错误 D．变量b的数据类型说明错误2、某VB程序的事件过程如下所示：Private Sub Command1_Click ( )Dim a As Integera = Val(Text1．Text)Text1．Text = Str(Int( a ))End Sub运行程序，单击按钮Command1后弹出如下图所示的错误提示。

导致该错误的原因可能是（）A．Int函数计算时出现错误 B．Val函数应用不正确C．窗体上缺少Text1文本框对象 D．变量a数据类型定义错误3、某Visual Basic程序段如下：Dim a(1 To 10) As IntegerDim i As Integera(1) = 1For i = 2 To 10a(i) = a(i - 1) * iNext i运行该程序段，会出现的错误提示为（A）下标越界（B）子程序或函数未定义（C）要求对象（D）溢出Interger类型范围在-32768~32767，而1到10相乘超出这个范围4、某Visual Basic程序如下：Private Sub Command1_Click()Dim a(1 To 10) As IntegerDim i As IntegerFor i = 1 To 10a(i) = i * iNext iList1.AddItem Str(a(i))End Sub运行程序，单击命令按钮Command1后，出现的错误提示为（A）下标越界（B）子程序或函数未定义（C）溢出（D）类型不匹5、有如下的Visual Basic程序：Private Sub Command1_Click()Const pi = 3.14Dim s As Single, r As Singler = Val(text1.Text)pi = 3.1415s = pi * r ^ 2Label1.Caption = "面积为" + Str(s)End Sub程序运行后，单击命令按钮Command1，出现如图所示的错误提示，下列原因分析正确的是（A）常量不能用小数（B）pi是常量，不允许赋值（C）文本框Text1中输入的数据不是常量（D）表达式结果超过了变量类型的范围6、某Visual Basic程序如下：Private Sub Command1_Click()Dim a(1 To 10) As IntegerDim i As IntegerFor i = 1 To 10a(i) = i * iNext iList1.AddItem Str(a(i))End Sub运行程序，单击命令按钮Command1后弹出如图所示的出错信息提示，此时程序正执行的语句是（A）For i = 1 To 10 （B）a(i) = i * i（C）Next i （D）List1.AddItem Str(a(i))7、某Visual Basic程序如下：Private Sub Command1_Click()Dim a As Single, b As SingleDim c As Singlea = 1b = 5c = Sqr(a - b)Text1.Text = Str(c)End Sub运行程序，单击命令按钮Command1后弹出如图所示的出错信息提示，此时程序正执行的语句是（A）a = 1 （B）b = 5（C）c = Sqr(a - b) （D）Text1.Text = Str(c)8、某同学正编写一个判断酒驾行为的Visual Basic程序，其窗体和代码窗口如下图所示。

根据代码窗口中的程序，要在程序运行时获取输入的x值，窗体上必须增加的对象是A. 标签Text1B. 标签Label2C. 文本框Text1D. 文本框Label29、运行下面的 Visual Basic程序，单击命令按钮 Command1，出现如下图所示的提示信息：Private Sub Command1_Click()Dim i As Integer, c As String, s As String, t As Strings = "2012 Hero"t = ""For i = 1 To Len(s)c = Mid(s, i, 1)If c >= "a" And c <= "z"t = t + cEnd IfNext iText1.Text = tEnd Sub出现该错误的原因是A．If语句缺少Then B．If语句缺少ElseC．变量t的数据类型说明错误 D．变量s的数据类型说明错误10、某VB程序在调试中弹出如图所示的错误窗口，产生该错误的可能原因是（）A．该VB程序代码中，缺少NextB．该VB程序窗体界面中，缺少某控件C．该VB程序代码中，某个常量或变量没有声明D．该VB程序设计软件没有正确安装11.运行如下Visual Basic程序，单击命令按钮Command1，出现如图所示的出错信息。

发生"下标越界"错误时所执行的语句是Private Sub Command1_Click()Dim a(0 To 5) As IntegerDim i As Integer '①a(0) = 1 '②For i = 1 To 5a(i) = 2 * a(i - 1) + 1 '③Next iText1.Text = Str(a(i)) '④End Sub（A）①（B）②（C）③（D）④12.运行如下Visual Basic程序，单击命令按钮Command1，出现如图所示的出错信息。

发生"下标越界"错误时所执行的语句是Dim a(0 To 5) As IntegerDim i As Integer '①a(0) = 1 '②For i = 1 To 6a(i) = 2 * a(i - 1) + 1 '③Next iText1.Text = Str(a(5)) '④End Sub（A）①（B）②（C）③（D）④13.某Visual Basic程序如下：Private Sub Command1_Click()Dim a(1 To 10) As IntegerDim i As IntegerFor i = 1 To 10a(i) = i * iNext iList1.AddItem Str(a(i))End Sub运行程序，单击命令按钮Command1后弹出如图所示的出错信息提示，此时程序正执行的语句是（A）For i = 0 To 10 （B）a(i) = i * i（C）Next i （D）List1.AddItem Str(a(i))14.运行如下Visual Basic程序，单击命令按钮Command1，出现如图所示的出错信息。

发生"除数为零"错误时所执行的语句是Private Sub Command1_Click()Dim a As Integer, b As Integer, c As Singlea = 2 '①b = a + 1 '②c = a / (b - 3) '③Text1.Text = Str(c) '④End Sub（A）①（B）②（C）③（D）④15.有如下的Visual Basic程序：Private Sub Command1_Click()Const pi = 3.14 '①Dim s As Single, r As Singler = Val(text1.Text) '②pi = 3.1415 '③s = pi * r ^ 2 '④Label1.Caption = "面积为" + Str(s)End Sub程序运行后，单击命令按钮Command1，出现如图所示的错误提示，下列原因分析正确的是（A）常量不能用小数（B）pi是常量，不允许赋值（C）文本框Text1中输入的数据不是常量（D）表达式结果超过了变量类型的范围16.题目如上题，问具体是哪条语句出错（A）①（B）②（C）③（D）④17.运行如下Visual Basic程序，单击命令按钮Command1，出现如图所示的出错信息。

发生"类型不匹配"错误时所执行的语句是Private Sub Command1_Click()Dim a As Integer, b As Integera = 10 '①b = 20 '②Text1.Text = "a+b=" + Val(a + b) '③End Sub '④（A）①（B）②（C）③（D）④18.某Visual Basic程序如下：Private Sub Command1_Click()Dim a As Single, b As SingleDim c As Singlea = 1b = 5c = Sqr(a - b)Text1.Text = Str(c)End Sub运行程序，单击命令按钮Command1后弹出如图所示的出错信息提示，此时程序正执行的语句是（A）a = 1 （B）b = 5（C）c = Sqr(a - b) （D）Text1.Text = Str(c)19.某Visual Basic程序如下：Private Sub Command1_Click()Dim i As Integer, sum As Integersum = 0For i = 10 To 2 Step -2sum = sum + iNext iText1.Text = Str(sum)End Sub运行程序，单击命令按钮Command1后弹出如图所示的出错信息提示，此时程序正执行的语句是（A）Sum = 0 （B）For i = 10 To 2 Step -2（C）sum = sum + i （D）Text1.Text = Str(sum)20.某Visual Basic程序如下：Private Sub Command1_Click()Dim a As Stringa = "d"a = Chr(Asc(a) - 32)Label1.Caption = aEnd Sub运行程序，单击命令按钮Command1后弹出如图所示的出错信息提示，此时程序正执行的语句是（A）a = "d" （B）End Sub（C）a = Chr(Asc(a) - 32) （D）Label1.Caption = a21.某Visual Basic程序如下：Private Sub Command1_Click()Dim x As Integer, i As IntegerFor i = 1 To 10 Step 3x = i * (i + 2)List1AddItem Str(x)Next iEnd Sub运行程序，单击命令按钮Command1后弹出如图所示的出错信息提示，引起该错误的语句是（A）For i = 1 To 10 Step 3 （B）x = i * (i + 2)（C）List1AddItem Str(x) （D）Next i22.某Visual Basic程序如下：Private Sub Command1_Click()Dim x As Integer, c As Integer, i As Integerc = 0For i = 1 To 12If 12 Mod i = 0 Thenc = c + 1End IfNext iText1.Tex = Str(c)End Sub运行程序，单击命令按钮Command1后弹出如图所示的出错信息提示，引起该错误的语句是（A）For i = 1 To 12 （B）c = c + 1（C）Next i （D）Text1.Tex = Str(c)23.下图所示是一个求和程序，程序界面上有标签Label1、标签Label2和一个命令按钮Command1。