VB.Net/Class/Class Define
Содержание
Class Composition
Imports System
Public Class MainClass
Shared Sub Main(ByVal args As String())
Dim s As New CStudent( _
"A", "B", 7, 24, 1949, 3, 12, 1988)
Console.WriteLine(s.ToStandardString() )
End Sub
End Class
" Encapsulates month, day and year.
Class CDay
Inherits Object
Private mMonth As Integer " 1-12
Private mDay As Integer " 1-31 based on month
Private mYear As Integer " any year
Public Sub New(ByVal monthValue As Integer, _
ByVal dayValue As Integer, ByVal yearValue As Integer)
mMonth = monthValue
mYear = yearValue
mDay = dayValue
End Sub " New
" create string containing month/day/year format
Public Function ToStandardString() As String
Return mMonth & "/" & mDay & "/" & mYear
End Function
End Class
" Represent student name, birthday and hire date.
Class CStudent
Inherits Object
Private mFirstName As String
Private mLastName As String
Private mBirthDate As CDay " member object reference
Private mHireDate As CDay " member object reference
" CStudent constructor
Public Sub New(ByVal firstNameValue As String, _
ByVal lastNameValue As String, _
ByVal birthMonthValue As Integer, _
ByVal birthDayValue As Integer, _
ByVal birthYearValue As Integer, _
ByVal hireMonthValue As Integer, _
ByVal hireDayValue As Integer, _
ByVal hireYearValue As Integer)
mFirstName = firstNameValue
mLastName = lastNameValue
" create CDay instance for employee birthday
mBirthDate = New CDay(birthMonthValue, birthDayValue, _
birthYearValue)
" create CDay instance for employee hire date
mHireDate = New CDay(hireMonthValue, hireDayValue, _
hireYearValue)
End Sub " New
" return employee information as standard-format String
Public Function ToStandardString() As String
Return mLastName & ", " & mFirstName & " Hired: " _
& mHireDate.ToStandardString() & " Birthday: " & _
mBirthDate.ToStandardString()
End Function " ToStandardString
End Class " CStudent
Define and use your own Time Class
Imports System
Public Class MainClass
Shared Sub Main(ByVal args As String())
Dim time As New CTime() " call CTime constructor
Console.WriteLine( "The initial universal times is: " & _
time.ToUniversalString() & vbCrLf & _
"The initial standard time is: " & _
time.ToStandardString() )
time.SetTime(13, 27, 6) " set time with valid settings
Console.WriteLine( "Universal time after setTime is: " & _
time.ToUniversalString() & vbCrLf & _
"Standard time after setTime is: " & _
time.ToStandardString() )
time.SetTime(99, 99, 99) " set time with invalid settings
Console.WriteLine( "After attempting invalid settings: " & vbCrLf & _
"Universal time: " & time.ToUniversalString() & _
vbCrLf & "Standard time: " & time.ToStandardString() )
End Sub
End Class
Class CTime
Inherits Object
Private mHour As Integer " 0 - 23
Private mMinute As Integer " 0 - 59
Private mSecond As Integer " 0 - 59
Public Sub New()
SetTime(0, 0, 0)
End Sub " New
Public Sub SetTime(ByVal hourValue As Integer, _
ByVal minuteValue As Integer, ByVal secondValue As Integer)
If (hourValue >= 0 AndAlso hourValue < 24) Then
mHour = hourValue
Else
mHour = 0
End If
If (minuteValue >= 0 AndAlso minuteValue < 60) Then
mMinute = minuteValue
Else
mMinute = 0
End If
If (secondValue >= 0 AndAlso secondValue < 60) Then
mSecond = secondValue
Else
mSecond = 0
End If
End Sub " SetTime
" convert String to universal-time format
Public Function ToUniversalString() As String
Return String.Format("{0}:{1:D2}:{2:D2}", _
mHour, mMinute, mSecond)
End Function " ToUniversalString
" convert to String in standard-time format
Public Function ToStandardString() As String
Dim suffix As String = " PM"
Dim format As String = "{0}:{1:D2}:{2:D2}"
Dim standardHour As Integer
" determine whether time is AM or PM
If mHour < 12 Then
suffix = " AM"
End If
" convert from universal-time format to standard-time format
If (mHour = 12 OrElse mHour = 0) Then
standardHour = 12
Else
standardHour = mHour Mod 12
End If
Return String.Format(format, standardHour, mMinute, _
mSecond) & suffix
End Function " ToStandardString
End Class " CTime
Nested Class Demo
Imports System
Public Class MainClass
Shared Sub Main()
Dim f1 As New Fraction(3, 4)
Console.WriteLine("f1: {0}", f1.ToString( ))
Dim fa As New Fraction.FractionArtist( )
fa.Draw(f1)
End Sub
End Class
Public Class Fraction
Private numerator As Integer
Private denominator As Integer
Public Sub New( _
ByVal numerator As Integer, ByVal denominator As Integer)
Me.numerator = numerator
Me.denominator = denominator
End Sub "New
Public Overrides Function ToString( ) As String
Return [String].Format("{0}/{1}", numerator, denominator)
End Function "ToString
" Nested Class
Class FractionArtist
Public Sub Draw(ByVal f As Fraction)
Console.WriteLine("Drawing the numerator: {0}", f.numerator)
Console.WriteLine( _
"Drawing the denominator: {0}", f.denominator)
End Sub "Draw
End Class "FractionArtist
End Class "Fraction
Your Complex Number Class
There is a minor bug though. The unary minus operator is incorrect.
Public Shared Operator -(ByVal c1 As Complex) As Complex
Return New Complex(c1.imaginaryPart, c1.realPart)
End Operator
This should be replaced with
Public Shared Operator -(ByVal c1 As Complex) As Complex
Return New Complex(-c1.realPart, -c1.imaginaryPart)
End Operator
and perhaps an additional function like
Public function Conjungate() As Complex
Return New Complex(realPart, -imaginaryPart)
End Function
And you might consider adding a .Length function equal to the current narrowing.
(And mathematically preferable replacing it, since converting complex->real isn"t well-defined)
Best regards
Eske Rahn
rahn at sol.dk
Imports System
Public Class MainClass
Shared Sub Main(ByVal args As String())
Dim X, Y As Complex
X = New Complex(1, 2)
Y = New Complex(3, 4)
Console.WriteLine( (X + Y).ToString )
Console.WriteLine( (X - Y).ToString )
Console.WriteLine( (X * Y).ToString )
Console.WriteLine( (X = Y).ToString )
Console.WriteLine( (X <> Y).ToString )
Console.WriteLine( (-X).ToString )
Dim abs_x As Double = CDbl(X)
Console.WriteLine( abs_x.ToString )
End Sub
End Class
Public Class Complex
Public realPart As Double
Public imaginaryPart As Double
" Constructors.
Public Sub New()
End Sub
Public Sub New(ByVal real_part As Double, ByVal imaginary_part As Double)
realPart = real_part
imaginaryPart = imaginary_part
End Sub
" ToString.
Public Overrides Function ToString() As String
Return realPart.ToString & " + " & imaginaryPart.ToString & "i"
End Function
" Operators.
Public Shared Operator *(ByVal c1 As Complex, ByVal c2 As Complex) As Complex
Return New Complex( _
c1.realPart * c2.realPart - c1.imaginaryPart * c2.imaginaryPart, _
c1.realPart * c2.imaginaryPart + c1.imaginaryPart * c2.realPart)
End Operator
Public Shared Operator +(ByVal c1 As Complex, ByVal c2 As Complex) As Complex
Return New Complex( _
c1.realPart + c2.realPart, _
c1.imaginaryPart + c2.imaginaryPart)
End Operator
Public Shared Operator -(ByVal c1 As Complex, ByVal c2 As Complex) As Complex
Return New Complex( _
c1.realPart - c2.realPart, _
c1.imaginaryPart - c2.imaginaryPart)
End Operator
Public Shared Operator =(ByVal c1 As Complex, ByVal c2 As Complex) As Boolean
Return (c1.realPart = c2.realPart) AndAlso (c1.imaginaryPart = c2.imaginaryPart)
End Operator
Public Shared Operator <>(ByVal c1 As Complex, ByVal c2 As Complex) As Boolean
Return (c1.realPart <> c2.realPart) OrElse (c1.imaginaryPart <> c2.imaginaryPart)
End Operator
Public Shared Operator -(ByVal c1 As Complex) As Complex
Return New Complex(c1.imaginaryPart, c1.realPart)
End Operator
Public Shared Narrowing Operator CType(ByVal c1 As Complex) As Double
Return System.Math.Sqrt(c1.realPart * c1.realPart + c1.imaginaryPart * c1.imaginaryPart)
End Operator
End Class