VB上机试题及答案复习进程

V B上机试题及答案

上机操作练习题

1．某数组有20个元素，其值为随机产生的两位整数。现要求将前10个元素与后10个元素对换。即第1个元素与第20个元素互换，第2个数与第19个元素互换，…，第10个元素与第11个元素互换。在窗体上输出数组原来各元素的值与对换后各元素的值。

Option explicit

Dim a(1 to 20) as integer, I as integer, j as integer, t as integer

Private Sub Form_Load()

Show

Print "原始数组是："

Randomize

For i = 1 To 20

a(i) = Int(Rnd * 90) + 10

Print a(i);

If i Mod 10 = 0 Then Print

Next i

Print

Print "现在数组是："

For i = 1 To 10

j = 21 - i

t = a(i): a(i) = a(j): a(j) = t

Next i

For i = 1 To 20

Print a(i);

If i Mod 10 = 0 Then Print

Next i

End Sub

2．从数组中删除一个数。先定义一个一维数组，大小、数组的值自定。从键盘上输入一个数，若这个数在数组当中，就把它删除；若这个数不在数组中，提示“该数不在数组中”

注意：1）如果数组中存在多个与该数相同的元素，每一个都能删除；

2）能实现多次删除

Private Sub Form_Load()

Show

ReDim a(9) As Integer

m = 1

Print "原来数组为："

For i = 0 To 9

a(i) = InputBox("请输入第" & m & "个数：")

Print a(i);

m = m + 1

Next i

Print

n = InputBox("查找的数是：")

i = 0: flag = False

Do

If a(i) = n Then

j = i: flag = True

For k = j To UBound(a) - 1

a(k) = a(k + 1)

Next k

ReDim Preserve a(UBound(a) - 1)

i = i - 1

End If

i = i + 1

Loop While (i <= UBound(a))

If flag = False Then

MsgBox n & "不在该数组中"

Else

Print "删除" & n & "后的数组是:"

For i = 0 To UBound(a)

Print a(i);

Next i

End If

End Sub

3．数组a中存放着升序排列的数据，使用array赋值，将inputbox输入的新数插入到数组中，插入后数组仍有序。

注意：要求利用动态数组，能够实现多次插入

Private Sub Form_Load()

Show

n = 8: ReDim a(n)

a = Array(5, 15, 23, 52, 68, 88, 90, 99)

n = n + 1: ReDim Preserve a(n)

m = InputBox("请输入要插入的数据:")

For i = 1 To n - 1

If m < a(i) Then Exit For

Next i

For k = n To i + 1 Step -1

a(k) = a(k - 1)

Next k

a(k) = m

For i = 1 To n

Print a(i);

Next i

Print

End Sub

4．6个评委为4位歌手打分，分数介于1-100之间。去掉一个最高分，一个最低分，求出每位选手的最后得分。将4位歌手得分从高到低排列输出，同时输出该选手的编号。

如：歌手3 95分歌手 1 87分歌手 4 80分歌手 2 70分

Option Base 1

Private Type geshou

xuhao As String

fenshu(6) As Integer

score As Integer

pingjun As Integer

End Type

Dim singer(1 To 4) As geshou

Private Sub Command1_Click()

For i = 1 To 4

For j = 1 To 6

singer(i).fenshu(j) = Int(Rnd * 100)

singer(i).xuhao = "歌手" & i

Next

Next

Call paixu

End Sub

Private Sub paixu()

Dim p As geshou

For i = 1 To 4

For j = 1 To 5

For k = j To 6

If singer(i).fenshu(j) > singer(i).fenshu(k) Then

t = singer(i).fenshu(j)

singer(i).fenshu(j) = singer(i).fenshu(k)

singer(i).fenshu(k) = t

End If

Next

Next

Next

For i = 1 To 4

For j = 2 To 5

singer(i).score = singer(i).score + singer(i).fenshu(j)

Next

singer(i).pingjun = singer(i).score / 4

Next

For i = 1 To 3

For j = i To 4

If singer(i).score < singer(j).score Then

p = singer(i): singer(i) = singer(j): singer(j) = p

End If

Next

Next

For i = 1 To 4

Print singer(i).xuhao & "得分：" & singer(i).pingjun

Next

End Sub

Private Sub Form_Load()

End Sub

10个评委给10个选手打分

Private Sub Form_Load()

Show

n = UBound(b)

For i = 1 To 10

For j = 1 To 10

a(i, j) = Val(InputBox("请第" & j & "位评委给第" & i & "位选手打分："))

Next j

For i = 1 To 10

max = a(i, 1): sum = 0

min = a(i, 1): ave = 0

For j = 1 To 10

If a(i, j) > max Then max = a(i, j)

If a(i, j) < min Then min = a(i, j)

sum = sum + a(i, j)

Next j

ave = (sum - max - min) / (n - 2)

b(i) = ave

Next i

For i = 1 To n - 1

For j = i + 1 To n

If b(i) < b(j) Then

t = b(i): b(i) = b(j): b(j) = t

End If

Next j

Next i

Print "选手的得分由高到低为："

For i = 1 To 10

Print b(i);

Next i

End Sub

5．编写函数求一元二次方程ax2+bx+c=0的解。

注意：要求考虑方程有两相等实根、两不等实根和两个虚根的情况。Dim a As Single, b As Single, c As Single

Dim s As Single

a = InputBox("请输入a")

b = InputBox("请输入b")

c = InputBox("请输入c")

s = b ^ 2 - 4 * a * c

If s < 0 Then

MsgBox ("方程无解")

ElseIf s = 0 Then

Print -b / 2 * a

Else

Print ((-b) + Sqr(s)) / 2 * a & " " & ((-b) - Sqr(s)) / 2 * a

End Sub

6. 任意输入一组字符，统计出大写字母多少个，小写字母多少个，数字多少个？要求用过程实现。

Call tongji(a, n, m, o)

Print "数字：" & n & Chr(13) & "小写：" & m & Chr(13) & "大写：" & o End Sub

Private Sub tongji(a As String, n As Integer, m As Integer, p As Integer)

For i = 1 To Len(a)

If Asc(Mid(a, i, 1)) > 47 And Asc(Mid(a, i, 1)) < 58 Then

n = n + 1

ElseIf Asc(Mid(a, i, 1)) > 96 And Asc(Mid(a, i, 1)) < 123 Then

m = m + 1

ElseIf Asc(Mid(a, i, 1)) > 64 And Asc(Mid(a, i, 1)) < 91 Then

p = p + 1

End If

Next

End Sub

7．随机产生一个5*5的矩阵，将主对角线和次对角线元素都置为1，并求出矩阵的四周元素之和，显示在列表框中。

Option Base 1

Private Sub Form_Load()

Dim a(5, 5) As Integer

Dim s As Integer

For i = 1 To 5

For j = 1 To 5

If i = j Or i = 6 - j Then

a(i, j) = 1

Else

a(i, j) = Int(Rnd * 1000)

End If

Text1.Text = Text1.Text & " " & a(i, j)

s = s + a(i, j)

Next

Text1.Text = Text1.Text & vbCrLf & vbCrLf

Next

List1.AddItem (s)

End Sub

8．编写一个函数，能将字母按下列规律译成密码：

A<-->Z a<-->z

B<-->Y b<-->y

即第1个字母与第26个字母互换，第i个字母与第(26-i+1)个字母互换。在文本框中任意输入一个字符串，调用该函数将密码显示在

另一个文本框中。

Private Sub Command1_Click()

Dim s1 As String

s1 = Text1.Text

Text2.Text = convert(s1)

End Sub

Private Function convert(s1 As String) As String

For i = 1 To Len(s1)

If Asc(Mid(s1, i, 1)) < 91 And Asc(Mid(s1, i, 1)) > 64 Then

convert = convert & Chr(91 - Asc(Mid(s1, i, 1)) + 64)

ElseIf Asc(Mid(s1, i, 1)) < 123 And Asc(Mid(s1, i, 1)) > 96 Then

convert = convert & Chr(123 - Asc(Mid(s1, i, 1)) + 96)

End If

Next

End Function

9．编写2个函数，分别求两个正整数的最大公约数和最小公倍数，用户任意输入两个数，采用函数嵌套调用，该函数将它们在窗体显示。

Private Sub Form_Load()

Text1 = "": Text2 = ""

End Sub

Private Sub Text1_KeyPress(KeyAscii As Integer)

If KeyAscii = 13 Then Text2.SetFocus

End Sub

Private Sub Text2_KeyPress(KeyAscii As Integer)

Dim m As Integer, n As Integer, r As Integer, t As Integer, x

Cls

If KeyAscii = 13 Then

m = Text1.Text

n = Text2.Text

If m < n Then

t = m: m = n: n = t

End If

r = m Mod n

While r <> 0

m = n: n = r: r = m Mod n

Wend

Print

If m < 0 Or n < 0 Then

x = MsgBox("请输入正数", vbCritical + vbOKCancel)

If x = vbCancel Then

End

Else

Text1 = "": Text2 = ""

Text1.SetFocus

End If

Else

Print Text1.Text & "和" & Text2.Text & "的最大公约数是："; n

End If

End If

End Sub

10. 编写计算阶乘的Function过程，利用e x的下列公式计算e（直到最后一项小于10-6为止）的近似值。

e x≈1+x/1!+x2/2!+x3/3!+…+x n/n!

Option Explicit

Private Sub Form_Load()

Show

Dim x As Integer, n As Integer, s As Double

x = InputBox("请输入一个数：")

n = 1: s = 1

Do

s = s + x ^ n / (jiecheng(n))

n = n + 1

Loop Until x ^ n / (jiecheng(n)) < 10 ^ (-6)

Print s

End Sub

Public Function jiecheng(n As Integer) As Double

Dim i As Integer, s As Double

s = 1

For i = 1 To n

s = s * i

Next i

jiecheng = s

End Function

11．输入整数N，显示具有N行的杨辉三角形，要求按正三角形的形式在图片框中显示。

Option Explicit

Private Sub Form_Load()

WindowState = 2

Show

Dim a(), n As Integer, i As Integer, j As Integer, g As Integer, e As Integer

n = InputBox("请输入一个数：")

ReDim a(n, n)

e = 80

For i = 1 To n

e = e - 5: g = e

For j = 1 To n

If j > i Then

a(i, j) = 0

Else

If i = j Then

a(i, j) = 1

Else

a(i, j) = a(i - 1, j) + a(i - 1, j - 1)

End If

End If

If a(i, j) = 0 Then

Exit For

Else

Picture1.Print Tab(g); a(i, j);

g = g + 10

End If

Next j

Picture1.Print

Next i

End Sub

Private Sub Picture1_Click()

End Sub

12．编写一个过程，输出以下菱形图形：

A

BBB

CCCCC

DDDDDDD

CCCCC

BBB

A

主程序输入一个奇数（>＝3），调用过程在窗体上输入图形。

Private Sub Command1_Click()

Dim n As Integer

n = InputBox("")

If n Mod 2 = 0 Or n <= 3 Then

MsgBox ("错误")

Else

Call draw(n)

End If

End Sub

Sub draw(n As Integer)

For i = 1 To (n + 1) / 2

s = Chr(64 + i)

Print Tab(41 - i + 1); String(2 * (i - 1) + 1, s)

Next

c = 1

For j = (n - 1) / 2 To 1 Step (-1)

c = c + 1

s = Chr(64 + i - c)

Print Tab(41 - i + c + 1); String(2 * (j - 1) + 1, s)

Next

End Sub

13．编写一个将十进制转换为二进制字符串输出的函数。调用函数计算用户输入一个十进制数，在文本框中输出二进制值。

注意：输入数据为负数，应该将符号位输出

如 -13 结果 -1101

Option Base 1

Dim a()

Private Function convert(y) As String

Dim i As Integer

i = 1

ReDim a(i)

x = Abs(y)

Do While x <> 0

ReDim Preserve a(i)

a(i) = x Mod 2

If a(i) = 1 Then

x = (x - 1) / 2

Else

x = x / 2

End If

i = i + 1

Loop

ReDim Preserve a(UBound(a))

If y < 0 Then

For i = 1 To UBound(a)

convert = convert & a(i)

Next

convert = "-" & convert

Else

For i = 1 To UBound(a)

convert = convert & a(i)

Next

End If

End Function

Private Sub Command1_Click()

Dim y As Integer

Text1.Text = ""

y = InputBox("请输入十进制数字")

Text1.Text = convert(y)

End Sub

Private Sub Form_Load()

End Sub

14．输入一个整数N，产生N个随机数（范围1—10*N），然后采用任何2种算法实现由小到大的排序。将排序前后的数据显示出来。

Option Base 1

Private Sub Command1_Click()

Dim a() As Integer, n As Integer

n = InputBox("请输入数列项数")

ReDim a(n)