I have a For Each loop that is only iterating 1 element. It begins with the 6th element out of 32 in my test, and happens to be one where the comp.includeMe evaluates to True. After the outer if statement is executed, it begins the 2nd iteration but exits the loop and returns immediately after the comp.includeMe evaluated to false. No errors or warnings are present, and I have verified that there are elements in the components object. Can anyone explain what I am doing wrong, and why this syntax doesn't work?
Public Class BOM
Public Property components as New List(Of Component)
Public Function TotalArea(ByVal adjusted As Boolean) As Double
Dim total As Double = 0
For Each comp As Component In components
If comp.includeMe = True Then
If adjusted Then
total += comp.GetAdjustedSize() * comp.quantity
Else
total += comp.area * comp.quantity
End If
End If
Next
Return total
End Function
public sub Add(byval comp as Component)
components.add(comp)
end sub
End Class
Public Class Component
Public Property quantity as Integer
Public Property area as Double
Public Property includeMe as Boolean
...
End Class
' object construction
Dim bomlist as New BOM
bomlist.add(comp)
After digging a little deeper, it seems that the foreach statement is recognizing the first if statement and pulls values only if it is true. I realized I only had only had one component with the includeMe Boolean set to true. After I set other components to true as well, I observed that the For Each iterates exactly the number of times as the number of components with includeMe = True
I'd suggest adding some debug statements to assist with debugging:
Public Class BOM
Public Property components as New List(Of Component)
Public Function TotalArea(ByVal adjusted As Boolean) As Double
Dim total As Double = 0
Debug.Print(components.Count)
For Each comp As Component In components
Debug.Print(comp.includeMe)
If comp.includeMe = True Then
If adjusted Then
total += comp.GetAdjustedSize() * comp.quantity
Else
total += comp.area * comp.quantity
End If
End If
Next
Return total
End Function
public sub Add(byval comp as Component)
components.add(comp)
end sub
End Class
Related
I was wondering if you could help me understand how to create a Card object (with a value and suit) and use 52 of those cards to make an object called deck.
I have created my card class how do I initialize every card inside the deck class? Should I do it one by one? How do I link all those cards to one deck.
Thanks
As it happen I did read your previous question earlier today.
First, create a suit enum.
Public Enum Suit As Integer
Hearts = 1
Diamonds = 2
Clovers = 3
Spades = 4
End Enum
Then create the card class. Notice that the properties are read only as a card never changes its value. (Maybe not true if you're a magician)
Public Class Card
Public Sub New(suit As Suit, value As Integer)
Me.m_suit = suit
Me.m_value = value
End Sub
Public ReadOnly Property Suit() As Suit
Get
Return Me.m_suit
End Get
End Property
Public ReadOnly Property Value() As Integer
Get
Return Me.m_value
End Get
End Property
Private m_suit As Suit
Private m_value As Integer
End Class
Finally, create the deck class and populate 52 cards.
Public Class Deck
Public Sub New()
Dim cards = New Card(52 - 1) {}
Dim num As Integer = 0
For s As Integer = 1 To 4
For v As Integer = 1 To 13
cards(num) = New Card(CType(s, Suit), v)
num += 1
Next
Next
Me.m_cards = New Collections.ObjectModel.ReadOnlyCollection(Of Card)(cards)
End Sub
Public ReadOnly Property Cards() As Collections.ObjectModel.ReadOnlyCollection(Of Card)
Get
Return Me.m_cards
End Get
End Property
Private ReadOnly m_cards As Collections.ObjectModel.ReadOnlyCollection(Of Card)
End Class
You need two Enumerations and two Classes:
Enumerations
CardFaceValue - with values ranging from Ace-10 (inclusive), Jack, Queen, King.
CardFaceType - with values Hearts, Spades, Clubs, Diamonds
Classes
Deck - Has one property to contain the collection of all cards
Cards - of Type Array of Cards, sized 52.
Card - Has two properties
CardFaceValue
CardFaceType
In the constructor of the Deck class run a loop within a loop. The outer loop will run for 4 times for each of the CardFaceType enumeration, and the inner loop will run for 13 times for cards 1-10, J, Q, K.
With these loops iterate through the enumeration values and add cards to your Deck.
This is just a quick draft of what I envision
You'll need the card class first.
Public Class Card
Private cSuit As String
Private cValue As Integer
Public Property suit() As String
Get
Return cSuit
End Get
Set(ByVal value As String)
cSuit = value
End Set
End Property
Public Property value() As Integer
Get
Return cValue
End Get
Set(ByVal value As Integer)
value = cValue
End Set
End Property
Public Sub New(ByVal TheSuit As String, ByVal TheValue As Integer)
cSuit = TheSuit
cValue = TheValue
End Sub
Then you can make a new object for each card and add it to the deck collection.
Dim Deck As New List(Of Card)
Dim Suit As String = "Spade"
Dim Value As Integer = 11
Dim AceOfSpades As New Card(Suit, Value)
Deck.Add(AceOfSpades)
I have a VB.NET class library, ConsoleControls, which has a few class objects designed to imitate Forms objects in Console mode. For example, there is a ProgressBar class which draws an ASCII progress bar set at a certain value. I've been using this library in my main project, TheGame.
The code is functional, but when I use the class objects and methods in my main project, I've been getting strange behaviour when debugging. For example, when I call the ProgressBar class's Draw method, the yellow arrow showing which line is about to be executed appears at the End Sub for that method. Then of all things it starts running through a completely different class, TextBox, which has nothing to do with ProgressBar. It repeats certain lines multiple times. It's as if the debugger is running a completely different portion of code to what it shows me it's running.
Here's the ProgressBar class:
Public Class ProgressBar
Public InactiveColour As ConsoleColor
Public ActiveColour As ConsoleColor
Public Position As Point
Public Length As Integer
Public Value As Integer
Public MaxValue As Integer
Public Sub New(_Position As Point, _Length As Integer, _InactiveColour As ConsoleColor, _ActiveColour As ConsoleColor)
Position = _Position
Length = _Length
InactiveColour = _InactiveColour
ActiveColour = _ActiveColour
End Sub
Public Sub SetValue(_Value As Integer, _MaxValue As Integer)
Value = _Value
MaxValue = _MaxValue
End Sub
Public Sub IncrementValue()
If Value + 1 <= MaxValue Then Value += 1
End Sub
Public Sub DecrementValue()
If Value - 1 >= 0 Then Value -= 1
End Sub
Public Sub Draw()
Dim ActiveBars, InactiveBars As Integer
Dim Divisor As Double
Divisor = MaxValue / Length
ActiveBars = CInt(Value / Divisor)
InactiveBars = Length - ActiveBars
Console.SetCursorPosition(Position.X, Position.Y)
Console.ForegroundColor = ActiveColour
For i = 1 To ActiveBars
Console.Write(Block)
Next
Console.ForegroundColor = InactiveColour
For i = 1 To InactiveBars
Console.Write(Block)
Next
Console.ResetColor()
End Sub
End Class
And here's the code that does weird things in my main project:
Dim PlayerHealthBar As ProgressBar
PlayerHealthBar = New ProgressBar(New Point(30, 4), 32, ConsoleColor.DarkGray, ConsoleColor.White)
PlayerHealthBar.SetValue(1, 10)
PlayerHealthBar.Draw()
Any suggestions as to what may be going on?
Dim index As Integer
Dim choice As String
Dim total As Integer
total = 0
index = NumericUpDown1.Value
Dim arr(4) As Integer
arr(0) = 10
arr(1) = 5
arr(2) = 21
arr(3) = 33
If index > 0 Then
choice = (Combobox1.SelectedItem.ToString + " x " + NumericUpDown1.Value.ToString)
ListBox1.Items.Add(choice)
CheckedListBox1.Items.Add(choice)
total += arr(Combobox1.SelectedIndex) * index
TotalLabel.Text = total.ToString()
Else
MsgBox("error.")
End If
I can calculate the total of single choice, but fail to accumulate to sum.
What's wrong of the code?
Current Situation:
Step 1:
choose arr(0), index = 2
total = 20
Step 2:
choose arr(2), index = 1
total = 21
Correct Situation:
Step 1:
choose arr(0), index = 2
total = 20
Step 2:
choose arr(2), index = 1
total = 41
You'll need a either a global variable or a class with a public variable. You should create a Transaction class to store the data about the transaction and probably a Product class to store the data about the product. What you put in it is up to you, but I'd start out with something like this:
Public Class Transaction
Private _productsList As List(of Product)
Private _transationNumber As Integer
'...more stuff...
'you'll want to remember what products are in your "cart" for the transaction
Public Property ProductsList As List(of Product)
'your get/set accessors
End Property
Public Property TransactionNumber As Integer
'your get/set accessors
End Property
Public Property TotalTransactionCost() As Double
Get
'this will sum of the prices of all of the products you have stored in your
'list of products for this transaction
Return _productsList.Sum(product => product.Price)
End Get
End Property
Public Sub New()
'...constructor stuff
End Sub
Public Sub AddProductToTransaction(byval product)
_productsList.Add(product)
End Sub
End Class
Public Class Product
Private _price As Double
Private _productName As String
Private _UPC As String
Public Property Price() As Double
'your get/set accessors
End Property
Public Property ProductName() As String
'your get/set accessors
End Property
Public UPC As String () As String
'your get/set accessors
End Property
Public Sub New()
'constructor stuff
End Sub
End Class
These are a couple class shells to get you started. If you're serious about making a product, this is a step in the right direction. If you're going to write code, write it the right way.
If you're just looking for a quick and dirty solution, you can declare a global variable and just keep a running sum. Just don't forget to clear it out before you start a new transaction.
You'll want to do something like:
Private TransactionCost As Double in your form outside of all your methods.
Again, I would recommend the first way of going about things. You'll need at least those two classes and they'll definitely be more fleshed out for a real product.
I hope this helps and answers your question. If it does, hit me with an upvote and accept the answer. Welcome to SO.
I have a problem with getting variable from another class and cannot understand what to do with interface`s functions which have already existed in another class.
What I have:
Form where clicking on a button I should see reversed string:
(I want to call pooraja.StringReverse which is below)
Private Sub btnPoora1_Click(sender As System.Object, e As System.EventArgs) _
Handles btnPoora1.Click
'Dim text As PrjTekstiPooraja.ITeisendused = New PrjTekstiPooraja.CtekstiPooraja
Dim text As PrjTekstiPooraja.ITeisendused = New PrjTekstiPooraja.CtekstiPooraja
Dim pooraja As PrjTekstiPooraja.ITeisendused = New PrjTekstiPooraja.CAlgrotimilinePooraja
text.strText = txtSisendTekst.Text
txtValjundTekst1.Text = pooraja.stringReverse
text.intStart = 1
text.intEnd = Len(txtSisendTekst.Text)
ascFSymbol.Text = text.ascFirstSymbol
ascLSymbol.Text = text.ascLastSymbol()
End Sub
CtekstiPooraja:
(Thiss class will be used to store data.Under data I mean strPooratavText. Data will be used in CAlgoritmilinePooraja)
Public Class CtekstiPooraja
Implements ITeisendused
Public intStartSymbol As Integer
Public intEndSymbol As Integer
Public strPooratavText As String
Private Property intEnd As Integer Implements ITeisendused.intEnd
Get
Return intEndSymbol
End Get
Set(ByVal value As Integer)
intEndSymbol = value
End Set
End Property
Private Property intStart As Integer Implements ITeisendused.intStart
Get
Return intStartSymbol
End Get
Set(ByVal value As Integer)
intStartSymbol = value
End Set
End Property
Public Function pooraText() As String Implements ITeisendused.pooraText
Return StrReverse(strPooratavText)
End Function
Public Property strText As String Implements ITeisendused.strText
Get
Return strPooratavText
End Get
Set(ByVal value As String)
strPooratavText = value
MsgBox(strPooratavText)
End Set
End Property
Public Sub teisendaText(ByRef strSisendText As String) Implements ITeisendused.teisendaText
strPooratavText = StrReverse(strSisendText)
End Sub
Public Function ascFirstSymbol() As String Implements ITeisendused.ascFirstSymbol
Return Asc(GetChar(strPooratavText, intStartSymbol))
End Function
Public Function ascLastSymbol() As String Implements ITeisendused.ascLastSymbol
Return Asc(GetChar(strPooratavText, intEndSymbol))
End Function
Public Function stringReverse() As String Implements ITeisendused.stringReverse
Return Nothing
End Function
End Class
CAlgrotimilinePooraja:
(This class will be called by form button. There I need to use stringReverse function with data from CtekstiPooraja. The problem is that everywhere is used the same interface and there is some functions and procedures from this interface which isnt necessary. I dont know what value should return these unused functions/procedures. Just using "return Nothing or return 0/ "" is bad idea, may be there is possible somehow referenceto to CTekstiPooraja functions/procedures variables")
Public Class CAlgrotimilinePooraja
Implements ITeisendused
Private x As New PrjTekstiPooraja.CtekstiPooraja
Public Function stringReverse() As String Implements ITeisendused.stringReverse
MsgBox(x.strPooratavText)
Dim i As Integer = 0
Dim j As Integer
Dim characters(j) As Char
Dim newString(j) As Char
characters = x.strPooratavText.ToCharArray()
newString = x.strPooratavText.ToCharArray()
Do While i <= j - 1
newString(i) = characters(j - 1)
newString(j - 1) = characters(i)
i += 1
j -= 1
Loop
Return newString
End Function
Public Function ascFirstSymbol() As String Implements ITeisendused.ascFirstSymbol
Return x.ascFirstSymbol()
End Function
Public Function ascLastSymbol() As String Implements ITeisendused.ascLastSymbol
Return Nothing
End Function
Public Property intEnd As Integer Implements ITeisendused.intEnd
Get
Return x.intEndSymbol
End Get
Set(ByVal value As Integer)
End Set
End Property
Public Property intStart As Integer Implements ITeisendused.intStart
Get
Return x.intStartSymbol
End Get
Set(ByVal value As Integer)
End Set
End Property
Public Function pooraText() As String Implements ITeisendused.pooraText
Return x.pooraText()
End Function
Public Property strText As String Implements ITeisendused.strText
Get
Return x.strPooratavText
End Get
Set(ByVal value As String)
End Set
End Property
Public Sub teisendaText(ByRef strSisendText As String) Implements ITeisendused.teisendaText
x.strPooratavText = StrReverse(strSisendText)
End Sub
End Class
MyInterface:
Public Interface ITeisendused
Property intStart As Integer
Property intEnd As Integer
Property strText As String
Function pooraText() As String
Function ascFirstSymbol() As String
Function ascLastSymbol() As String
Function stringReverse() As String
Sub teisendaText(ByRef strSisendText As String)
End Interface
I cannot understand how to get variable strPooratavText from CTekstiPooraja to CAlgrotimilinePooraja. Usually that instancewhich I create worked but not now. And I cannot understand what to do with already existed function and procedures in CAlgoritmilinePooraja when the same function and procedures has in another class. Maybe, it is possible to reference them somehow to existed functions/procedures in CTekstiPooraja? Could you explain me how to id, already tired to surf Internet to find a solution for it, have already try a lot.
Well, I think you have a fundamental problem with understanding interfaces. They describe data and behavior, it should be extremely rare to want to implement part of an interface.
That said, if you do want to implement part of an interface, instead of returning bogus data, throw an exception for behavior you don't implement.
Your specific problem is that CAlgoritmilinePooraja works on an instance of CtekstiPooraja, but it creates a new instance instead of using an existing one. Add
Sub New(incomingX as CtekstiPooraja)
x = incomingX
End Sub
to CAlgoritmilinePooraja. And then in your event, use....
Dim text As PrjTekstiPooraja.CtekstiPooraja = New PrjTekstiPooraja.CtekstiPooraja
text.strText = txtSisendTekst.Text
Dim pooraja As PrjTekstiPooraja.ITeisendused = New PrjTekstiPooraja.CAlgrotimilinePooraja(text)
That is the minimum change to your design that gets what you want to happen to happen but it's problably not what you should do. Other than implementing strReverse, CtekstiPooraja seems to be what you want, CAlgrotimilinePooraja looks to do just one thing, the actual string reversal.
I would move the implementation of strReverse into CtekstiPooraja, and then eliminate CAlgrotimilinePooraja.
PS I would try to stick to English for class names as well as functions and variables.
Using VB.Net
I have about 60 Child forms
Each have a variable with same name.
In Main form I want to set the value of the variable of the active child.
One way of doing that is like
Select Case Me.ActiveMdiChild.Name
Case "formName"
frmformName.Variable=0
I donot want to do that as it involves writing many cases and I may miss some.
Is there some other way of doing it .
I tried
Dim O as Object = Me.ActiveMdiChil
O.VariableName= 0
and its various variants but its not working
Another way to do that is with an Interface, example:
Public Interface IChildVariable
Property Variable() As Integer
End Interface
Public Class Form1
Implements IChildVariable
Private _MyVariable As Integer
Public Property Variable() As Integer Implements IChildVariable.Variable
Get
Return _MyVariable
End Get
Set(ByVal value As Integer)
_MyVariable = value
End Set
End Property
End Class
Then you can just have a single check point:
If TypeOf Me.ActiveMdiChild Is IChildVariable Then
DirectCast(Me.ActiveMdiChild, IChildVariable).Variable = 0
Else
''Throw Exception
End If