VB程序题(4).docx

1在窗体Form1中实现函数MarkClass。mark参数为成绩，函数对成绩的评价。成绩评价方法为：90及以上优秀，80及以上良好，70及以上中等，60及以上及格，60以下不及格。Public Function MarkClass(mark As Long) As StringEnd FunctionPublic Function markclass(mark As Long) As StringDim s$If mark = 90 Thens = 优秀 ElseIf mark = 80 Thens = 良好 ElseIf mark = 70 Thens = 中等 ElseIf mark = 60 Thens = 及格 Else:s = 不及格End Ifmarkclass = sEnd Function2在窗体Form1中实现函数MySgn。当参数x0时，函数MySgn返回1；当参数x 0 Thenmysgn = 1ElseIf x = 0 Thenmysgn = 0Elsemysgn = -1End IfEnd Function3在窗体Form1中实现函数TriangleArea。a,b,c三个参数为三角形三条边，若三边能构成三角形，函数返回三角形面积；否则返回0。提示： 海伦公式为： , Public Function TriangleArea(a As Long, b As Long, c As Long) As DoubleEnd FunctionPublic Function trianglearea(a As Long, b As Long, c As Long) As DoubleDim s%, p%p = (a + b + c) / 2s = Sqr(p * (p - a) * (p - b) * (p - c)If a + b = c Or a + c = b Or b + c = a Thentrianglearea = 0Elsetrianglearea = sEnd IfEnd Function4在窗体Form1中实现函数TriangleClass。a,b,c三个参数为三角形三条边，函数返回三角形的形状。可能的三角形形状为以下4种：等边三角形，等腰三角形，一般三角形，不构成三角形。Public Function TriangleClass(a As Long, b As Long, c As Long) As StringEnd FunctionPublic Function triangleclass(a As Long, b As Long, c As Long) As StringDim s$If a + b = c Or b + c = a Or a + c b And a c Then max = aIf b a And b c Then max = bIf c b And c a Then max = cIf a b And a c Then min = aIf b a And b c Then min = bIf c b And c y Then Max = x Else Max = y End IfEnd Function7在窗体Form1中实现子程序Swap。Swap功能为：使第一个实参变量为较大值，第二个实参变量为较小值。Public Sub Swap(x As Long, y As Long)End SubSub swap(x As Long, y As Long) Dim t As Long If x 0: b3 = y Mod 400 = 0 leap = b1 And b2 Or b3 Select Case m Case 1, 3, 5, 7, 8, 10, 12 days = 31 Case 4, 6, 9, 11 days = 30 Case 2 If leap Then days = 29 Else days = 28 End If End SelectEnd Function9在窗体Form1中实现子程序MaxMin。参数中的a,b,c为三个数，通过max和min将找到的最大值和最小值以参数的形式返回。Public Sub MaxMin(a As Long, b As Long, c As Long, max as Long, min as Long)End SubSub MaxMin(a As Long, b As Long, c As Long, max As Long, min As Long) If a b And a c Then max = a If b a And b c Then max = b If c a And c b Then max = c If a b And a c Then min = a If b a And b c Then min = b If c a And c b Then min = cEnd Sub10在窗体Form1中实现函数Perfect。如果参数x为完全数，该函数返回True；否则返回False。（完全数：真因子（除自身以外的因子）之和为其本身）Public Function Perfect(x As Long) As BooleanEnd FunctionFunction perfect(x As Long) As BooleanDim i%, s%For