.NET (Core and Framework)

this.Hide()
LogonForm lf = new LogonForm()
result = lf.ShowDialog();
variable = lf.textbox1;
// etc ...

result=lf.ShowDialog();

variable=lf.textbox1

void someMethod()
{
    this.Hide()                     // hides the main form window
    LogonForm lf = new LogonForm()  // create a new LogonForm object
    result = lf.ShowDialog();       // call the LogonForm object's ShowDialog() method, which
                                    // shows the LogonForm window and waits for user input
                                    // user pressed OK (or cancel), window no longer on display
    variable = lf.textbox1;         // LogonForm object still exists, extract user input data
}                                   // LogonForm object gets disposed here

this.DialogResult = DialogResult.Cancel;

Bram van Kampen wrote:

I used Dispose(), not because I did not understand scope, but, because it was the only method (I know it is the WRONG one) I could find that at least removed the window, and broke out of the modal loop.

Bram van Kampen wrote:

The other queery stil stands. this.Hide()( called in the LogOn button handlers) hides the entire application, and not just the LogOn dialog. Is this a feature of the debug mode, or an error on my part.

Mike-MadBadger wrote:

I'm struggling to follow this explanation myself

Public Class MyParamaterBase
  Public Property Id As Guid
End Class

Public Class MyExtendedParameter
  Public Property Title as String
End Class

Public Class SomeConsumingClass

  Public Sub SomeMethod(TheParameter As MyParameterBase)
    ' to get to the "Title" property
    If TheParameter is MyExtendedParameter Then
      Console.WriteLine((TheParameter as MyExtendedParameter).Title)
    EndIf
  End Sub

End Class

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

Mike-MadBadger wrote:

I guess I could do the same thing by using an interface as the parameter?

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

Public Class Class1

    Private _param As Double

    Public Sub New(ByVal amount As Double)
        Me._param = amount
    End Sub

    Public Property Param() As Double
        Get
            Return Me._param
        End Get
        Set(value As Double)
            If Not value = Me._param Then
                Me._param = value
            End If
        End Set
    End Property

    Public Function ToGrey() As ToGreyMethods
        Return New ToGreyMethods(Me)
    End Function

    Public Class ToGreyMethods

        Private _outer As Class1

        Public Sub New(ByRef outer As Class1)
            Me._outer = outer
        End Sub

        Public Sub Increase(ByVal amount As Double)
            Me._outer.Param += amount
        End Sub

        Public Sub Decrease(ByVal amount As Double)
            Me._outer.Param -= amount
        End Sub
    End Class

End Class

Module Module1

    Sub Main()
        Dim thing As Class1 = New Class1(10)
        thing.ToGrey.Increase(5)
        Console.WriteLine(thing.Param.ToString())
        thing.ToGrey.Decrease(10)
        Console.WriteLine(thing.Param.ToString())
        Console.ReadKey()
    End Sub

End Module

'Output is:
'15
'5

Public Sub Example()
    Dim thing as Class1 = New Class1(10)
    Dim whoops as ToGreyMethods = thing.ToGrey()
    'I now have an instance of an object that I can start using to change the thing object without directly referring to thing, feels like a recipe for confusion...
End Sub

Mike-MadBadger wrote:

I now have an instance of an object that I can start using to change the thing object without directly referring to thing, feels like a recipe for confusion...

Public Class Class1

    Private _param As Double
    Private _methods As ToGreyMethods

    Public Sub New(ByVal amount As Double)
        Me._param = amount
        Me._methods = New ToGreyMethods(Me)
    End Sub

    Public Property Param() As Double
        Get
            Return Me._param
        End Get
        Set(ByVal value As Double)
            If Not value = Me._param Then
                Me._param = value
            End If
        End Set
    End Property

    Public ReadOnly Property ToGrey() As ToGreyMethods
        Get
            Return _methods
        End Get
    End Property

    Public Class ToGreyMethods

        Private _outer As Class1

        Public Sub New(ByRef outer As Class1)
            Me._outer = outer
        End Sub

        Public Sub Increase(ByVal amount As Double)
            Me._outer.Param += amount
        End Sub

        Public Sub Decrease(ByVal amount As Double)
            Me._outer.Param -= amount
        End Sub
    End Class

End Class

Module Module1

    Sub Main()
        Dim thing As Class1 = New Class1(10)
        thing.ToGrey.Increase(5)
        Console.WriteLine(thing.Param.ToString())
        thing.ToGrey.Decrease(10)
        Console.WriteLine(thing.Param.ToString())

        ' Dim whoops2 As Font = Form1.Font <- now you got the same thing :)
        Dim whoops As Class1.ToGreyMethods = thing.ToGrey()

        Console.ReadKey()
    End Sub

End Module

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

Module GreyScaleExtentions
   Public Enum RBGMethods
       Average
       BlueChannel
       Decompose
       Desaturate
       Lightness
       RedChannel
       GreenChannel
   End Enum

   Public Enum LumaEnum
       BT709
       BT601
       GIMP
   End Enum

   ''' <summary>
   ''' Converts Color to greyscale equivalent using RGBGreyScaleMethod
   ''' </summary>
   ''' <param name="c"></param>
   ''' <param name="RGBMethod"></param>
   ''' <returns></returns>
   ''' <remarks></remarks>
   <Runtime.CompilerServices.Extension()> _
   Public Function ToGreyScale(ByVal c As Color, ByVal RGBMethod As RBGMethods) As Color

   End Function

   ''' <summary>
   ''' Converts Color to greyscale equivalent using luminosity method
   ''' </summary>
   ''' <param name="c"></param>
   ''' <param name="factors"></param>
   ''' <returns></returns>
   ''' <remarks></remarks>
   <Runtime.CompilerServices.Extension()> _
   Public Function ToGreyScale(ByVal c As Color, ByVal factors As LumaEnum) As Color

   End Function
End Module

Sub test()
   Dim c As Color = Color.FromArgb(230, 134, 231, 10)
   Dim gs As Color
   gs = c.ToGreyScale(LumaEnum.BT601)
   gs = c.ToGreyScale(RBGMethods.Average)
End Sub

Quote:

That one had occured but it meant that a user of the class would need to know that the overload without a method would give ByLuminosity, which was the bit that felt unintuitive.

Quote:

BTW, thanks for the piece, I assume that's how extension methods work?

Assembly assembly = Assembly.LoadFrom("MyLibrary.dll");

Type type = assembly.GetType("MyType");

object instanceOfMyType = Activator.CreateInstance(type);