18個VB經(jīng)典例題.doc

1、隨機產(chǎn)生三個100300之間的整數(shù)，判斷這三個整數(shù)是否能構(gòu)成三角形，如果可以，求三角形的面積。Dim x As Integer, y As Integer, z As IntegerDim c As Single, s As Singlex = Int(Rnd * 201 + 100)y = Int(Rnd * 201 + 100)z = Int(Rnd * 201 + 100)If x + y z And x + z y And y + z x Then c = (x + y + z) / 2 s = Sqr(c * (c - x) * (c - y) * (c - z) Print 三角形面積是： & s Else Print 構(gòu)不成三角形End If2、隨機產(chǎn)生0100之間的60名學生的數(shù)學分數(shù)，分別統(tǒng)計分數(shù)在、之間的學生人數(shù)。Dim a%, b%, c%, d%, e%, f%, g%, h%, i%, j%Dim x As SingleFor m = 1 To 60 產(chǎn)生60名學生的分數(shù) x = Rnd * 101 產(chǎn)生0100的分數(shù) Print x; If x = 90 Then a = a + 1 ElseIf x = 80 Then b = b + 1 ElseIf x = 70 Then c = c + 1 ElseIf x = 60 Then d = d + 1 ElseIf x = 50 Then e = e + 1 ElseIf x = 40 Then f = f + 1 ElseIf x = 30 Then g = g + 1 ElseIf x = 20 Then h = h + 1 ElseIf x = 10 Then i = i + 1 Else j = j + 1 End IfNext mPrint a, b, c, d, e, f, g, h, i, j3、我國有13億人口，按照人口年增長0.8%計算，多少年以后我國人口超過26億。Dim x As Double 人數(shù)一定要定義成雙精度的Dim n As Integerx = 1300000000n = 0Do While x = 0 Then x1 = (-b + Sqr(d) / (2 * a) 求方程的兩個根 x2 = (b + Sqr(d) / (2 * a) x1 = Format(x1, .#) 對根規(guī)范化輸出 x2 = Format(x2, .#)End IfPrint x1, x25、某次歌手大獎賽，共有10名選手，有10名評委打分。要求評委給10位選手打分，去掉一個最高分，去掉一個最低分，求出該選手的平均分。Dim i As IntegerDim j As IntegerDim max As Single, min As Single, sum As Single, aver As SingleFor i = 1 To 10 十個選手的成績 max = 0 min = 100 sum = 0 For j = 1 To 10 十個評委的分數(shù) x = Rnd * 101 產(chǎn)生0100的分數(shù) If x max Then max = x If x min Then min = x sum = sum + x Next j aver = (sum - max - min) / 8 Print aver;Next i6、求1到100以內(nèi)的素數(shù)。Dim i As Integer, j As Integer, prime As BooleanFor i = 1 To 100 prime = True For j = 2 To Sqr(i) 判斷一個數(shù)是否是素數(shù) If i Mod j = 0 Then prime = False End If Next j If prime Then 如果prime = True則i是素數(shù) Print i & 是素數(shù) Else Print i & 不是素數(shù) 如果prime = False則i不是素數(shù) End IfNext i7、求出100以內(nèi)的所有勾股數(shù)（勾股數(shù)為a2+b2=c2,c為自然數(shù)，且ab）Dim a As Integer, b As Integer, c As IntegerFor a = 1 To 100 For b = 1 To 100 For c = 1 To 100 If c * c = a * a + b * b And a b Then Print a; b; c; Print End If Next c Next bNext a8、把輸入的字符串逆序輸出。Dim str As String, strRe As StringDim i As Integer str = Text1.Text 原字符串 For i = 1 To Len(str) strRe = Mid(str, i, 1) & strRe 字符串逆序 Next i Text2.Text = strRe 逆序后的字符串9、隨機產(chǎn)生0100之間的60名學生的數(shù)學分數(shù)，分別統(tǒng)計分數(shù)在、之間的學生人數(shù)。（用數(shù)組實現(xiàn)）Dim i As Integer, s(1 To 10) As Integer, mark(1 To 60) As Integer,For i = 1 To 60 mark(i) =int( Rnd * 101) 隨機產(chǎn)生0100之間的分數(shù) Print mark(i); 輸出60個分數(shù) Select Case mark(i) Case Is 10 s(1) = s(1) + 1 Case Is 20 s(2) = s(2) + 1 Case Is 30 s(3) = s(3) + 1 Case Is 40 s(4) = s(4) + 1 Case Is 50 s(5) = s(5) + 1 Case Is 60 s(6) = s(6) + 1 Case Is 70 s(7) = s(7) + 1 Case Is 80 s(8) = s(8) + 1 Case Is 90 s(9) = s(9) + 1 Case Is max Then max = mark(i) 找出最大數(shù) If mark(i) mark(n + 1) Then mark(n + 2) = mark(n + 2) + 1Print mark(i); 輸出學生成績Next iPrint mark(n + 1); mark(n + 2) 輸出平均分與高于平均分的人數(shù)12、隨機生成包含10個數(shù)組元素的有序數(shù)組，然后第一個與第六個進行交換，第二個與第七個進行交換。，并把原數(shù)組以及交換后的數(shù)組分別在窗體上顯示出來。Dim s(1 To 10) As IntegerFor i = 1 To 10 產(chǎn)生10個數(shù)s(i) = Int(Rnd * 101)Print s(i); 輸出交換前的數(shù)值Next iPrintFor i = 1 To 5 實現(xiàn)交換t = s(i)s(i) = s(5 + i)s(5+ i) = tNext iFor i = 1 To 10Print s(i); 輸出交換后的數(shù)值Next i13、已知數(shù)組a=Array(1,4,8,5,10)，b(6)，通過數(shù)組a給數(shù)組b賦值；用選擇法按照升序?qū)?shù)組b排序，對排序后的數(shù)組插入元素6，使b數(shù)組有序；刪除元素5，并使數(shù)組元素個數(shù)減1。Option Base 1Private Sub Command1_Click()Dim b(1 To 6) As Integer, a As Varianta = Array(1, 4, 8, 5, 10)For i = 1 To 5 用數(shù)組A給數(shù)組B賦值b(i) = a(i)Print b(i); 輸出數(shù)組B的前5個元素Next iPrint b(6); 輸出數(shù)組B最后一個元素PrintFor i = 1 To 5 用選擇法對數(shù)組B升序排序Min = i For j = i + 1 To 6 If b(j) b(Min) Then Min = j Next jt = b(i): b(i) = b(Min): b(Min) = tNext iFor i = 1 To 6 輸出數(shù)組B的所有元素Print b(i);Next iPrint下面是對有序數(shù)組B插入元素6For j = 2 To 6 If 6 b(j - 1) Then 找出插入位置 For i = 1 To j - 1 插入位置以前的元素向前移動一個位置 b(i) = b(i + 1) Next i b(j - 1) = 6 在準確的位置插入6 End IfNext jFor i = 1 To 6 輸出插入6以后的數(shù)組B的所有元素 Print b(i);Next iPrintDim c() As Integer 定義數(shù)組C是一個動態(tài)數(shù)組ReDim c(1 To 6) As IntegerFor i = 1 To 6 c(i) = b(i)Next i下面是刪除元素5For i = 1 To 6If c(i) = 5 Then 如果數(shù)組C里面有5就進行刪除 For j = i To 5 把元素5后面的元素向前移動一個位置 c(j) = c(j + 1) Next j End If Next iReDim Preserve c(5) 只保留數(shù)組C里面前面的5個元素，達到了刪除目的For i = 1 To 5Print c(i); 輸出刪除5以后的數(shù)組元素Next iEnd Sub14、編寫一個無參數(shù)Sub過程Triangle，在窗體上輸出用“*”組成的如下圖所示的三角形圖案。被調(diào)過程Public Sub Triangle() 子過程Print *Print * * *Print * * * * *Print * * * * * * * Print * * * * * * * * *End Sub主調(diào)過程Private Sub Command1_Click()Call Triangle 調(diào)用子過程End Sub15、把上面的Triangle過程改造成帶參數(shù)的過程，使之能輸出任意行三角形圖案，并嘗試用兩種方法調(diào)用。被調(diào)過程Public Sub Triangle(n As Integer)For i = 1 To nPrint Tab(n - i); String(2 * i - 1, *);Next iEnd Sub主調(diào)過程Private Sub Command1_Click()Dim a As Integera = Val(InputBox(請輸入a)Call Triangle(a)End Sub16、編寫一個函數(shù)Prime，用于判斷一個自然數(shù)是否為素數(shù)。調(diào)用此函數(shù)輸出3100之間的所有的素數(shù)。（提示：函數(shù)Prime的類型使用布爾型）被調(diào)函數(shù)Public Function Prime(m As Integer, n As Integer) As BooleanDim i As Integer, j As Integer判斷m-n之間的所有素數(shù)For i = m To nPrime = TrueFor j = 2 To Sqr(i) 判斷一個數(shù)是否是素數(shù) If i Mod j = 0 Then Prime = False End If Next j If Prime Then 如果prime = True則i是素數(shù) Print i & 是素數(shù) Else Print i & 不是素數(shù) 如果prime = False則i不是素數(shù) End IfNext iEnd Function主調(diào)過程Private Sub Command1_Click()Dim a As Integer, b As IntegerDim c As Booleana = Val(InputBox(請輸入a)b = Val(InputBox(請輸入b)c = Prime(a, b)End Sub17、編寫函數(shù)，判斷某數(shù)是否是“水仙花數(shù)”。并用此函數(shù)輸出100999之間的所有的水仙花數(shù)、所謂的“水仙花數(shù)”是指一個3位數(shù)，其各位數(shù)字立方和等于該數(shù)本身。主調(diào)函數(shù)Private Sub Command1_Click()Dim a As Integer, b As IntegerDim c As Booleana = Val(InputBox(請輸入a)b = Val(InputBox(請輸入b)c = shuixianhua(a, b)End Sub被調(diào)函數(shù)Public Function shuixianhua(m As Integer, n As Integer) As BooleanDim i As Integer, j As Integer, x As Integer, y As Integer, z As Integer判斷m-n之間的所有水仙花數(shù)For i = m To nshuixianhua = Falsex = i 100 得到百分位的數(shù)y = (i - x * 100) 10 得到十位上的數(shù)z = i Mod 10 得到各位上的數(shù)If x 3 + y 3 + z 3 = i Then shuixianhua = TrueEnd IfIf shuixianhua Then Print i & 是水仙花數(shù)End IfNext iEnd Function18、編寫一個Find函數(shù)，能夠查找用戶輸入的數(shù)是否在一個隨機數(shù)組中，如果在數(shù)組中，則把它的位置顯示出來。Public Function Find(n As I