C# equivalent to DirectCast.

[HolyHarley]

I have been working in VB.net and have been using the combobox to
store data I need when the user selects an item. To do this, I have
been creating a class of some data.

Private Class Relationship

Public _code As String
Public _description As String
Public _default As Boolean

Public Sub New(ByVal sCode As String, ByVal sDescription As
String, ByVal bDefault As Boolean)

Me._code = sCode.Trim & ""
Me._description = sDescription.Trim & ""
Me._default = bDefault

End Sub

Public ReadOnly Property ListEntry() As String
Get
Return Me._code & " -- " & Me._description
End Get
End Property

End Class

I then load the combobox with data.

Private Sub LoadRelationship()

Try

Dim dr As SqlDataReader = _dropDown.GetRelationship

Me.cboRelationship.DisplayMember = "ListEntry"

While dr.Read

Me.cboRelationship.Items.Add(New
Relationship(dr.Item("code"), dr.Item("description"),
dr.Item("initial")))

End While

Catch ex As Exception
MsgBox(ex.ToString, MsgBoxStyle.Information +
MsgBoxStyle.OKOnly, "frmXXClientAddEdit.LoadRelationship Error...")
End Try

End Sub


Then when the user select an item, I cam access the code, description
or initial using the following:

If Me.cboRelationship.SelectedIndex <> -1 Then
.RelationCode = DirectCast(Me.cboRelationship.Items(Me.cboRelationship.SelectedIndex),
Relationship)._code
Else
.RelationCode = ""
End If

I found this very useful, especially when you expand the data stored
in the combobox.

In C# I have been able to get to the point where the data is stored in
the combobox, but I have not been able to get the data out. I will
need to access both the ID (int) field and the Description (string)
values, so the valuemember does not appear to cut it.

Appreciate any help.

Thanks.

Jeff

 

[Jon Skeet [C# MVP]]

I have been working in VB.net and have been using the combobox to
store data I need when the user selects an item. To do this, I have
been creating a class of some data.

In C# I have been able to get to the point where the data is stored in
the combobox, but I have not been able to get the data out. I will
need to access both the ID (int) field and the Description (string)
values, so the valuemember does not appear to cut it.

I haven't checked the spec, but I *suspect* that DirectCast in VB.NET
is equivalent to just casting in C#:

Description d = (Description) cboRelationship.SelectedItem;

 

[Henk Verhoeven]

Hi

I will use your VB example for the combo. I assume your question is about
the casting

If (this.cboRelationship.SelectedIndex <> -1 ){
this.RelationCode =
((Relationship)this.cboRelationship.SelectedItem)._code;

//or you can do this
this.RelationCode = (this.cboRelationship.SelectedItem as
Relationship)._code;

} else { this.RelationCode = ""; }

Henk

 

[Jon Skeet [C# MVP]]

I will use your VB example for the combo. I assume your question is about
the casting

If (this.cboRelationship.SelectedIndex <> -1 ){
this.RelationCode =
((Relationship)this.cboRelationship.SelectedItem)._code;

//or you can do this
this.RelationCode = (this.cboRelationship.SelectedItem as
Relationship)._code;

If you're not going to test the result against null, it's usually
clearer just to cast, IMO:

((Relationship)cboRelationship.SelectedItem)._code

I only use "as" if there's some doubt as to whether or not the value is
either null or some other type.

 

[Jeffrey Corrao]

Hank and Jon,
Thanks so much for your help. That is precisely what I was looking for.

For the most part, transitioning to C# has been pretty easy. Some of
the details are not always simple.

Thanks again,

Jeff

 

[David Anton]

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(www.instantcsharp.com). You'll be able to get any C# equivalents
just by typing the code snippet into the converter (without paying
anything!).

We also provide support for our Demo Edition, so if you have any
questions we'll answer them.