Use a System.Type in Generics?

[cmay]

Is this something you are not allowed to do?

I basically want to create an instance of a generic class where the
type T is not know at compile time.

e.g.

dim s as System.Type = GetMyType()
dim o as MyObj(Of s)


I have not found a way to do this, so I am guessing it is not possible.

[Herfried K. Wagner [MVP]]

Re: Use a System.Type in Generics?

"cmay" <cmay@walshgrou p.com> schrieb:[color=blue]
> I basically want to create an instance of a generic class where the
> type T is not know at compile time.
>
> e.g.
>
> dim s as System.Type = GetMyType()
> dim o as MyObj(Of s)[/color]

\\\
Dim GenericType As Type = GetType(List(Of ))
Dim ParameterTypes( ) As Type = {GetType(Intege r)}
Dim o As Object = _
Activator.Creat eInstance( _
GenericType.Mak eGenericType(Pa rameterTypes) _
)
///

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://classicvb.org/petition/>

[cmay]

Re: Use a System.Type in Generics?

Thanks HKW!


Herfried K. Wagner [MVP] wrote:[color=blue]
> "cmay" <cmay@walshgrou p.com> schrieb:[color=green]
> > I basically want to create an instance of a generic class where the
> > type T is not know at compile time.
> >
> > e.g.
> >
> > dim s as System.Type = GetMyType()
> > dim o as MyObj(Of s)[/color]
>
> \\\
> Dim GenericType As Type = GetType(List(Of ))
> Dim ParameterTypes( ) As Type = {GetType(Intege r)}
> Dim o As Object = _
> Activator.Creat eInstance( _
> GenericType.Mak eGenericType(Pa rameterTypes) _
> )
> ///
>
> --
> M S Herfried K. Wagner
> M V P <URL:http://dotnet.mvps.org/>
> V B <URL:http://classicvb.org/petition/>[/color]

[Cor Ligthert [MVP]]

Re: Use a System.Type in Generics?

Herfried,

I am curious how I can use this Generic List of a typed class, while I don't
know the members of the class?

Can you give me an example?

Cor

"Herfried K. Wagner [MVP]" <hirf-spam-me-here@gmx.at> schreef in bericht
news:OfAidWNiGH A.1208@TK2MSFTN GP02.phx.gbl...[color=blue]
> "cmay" <cmay@walshgrou p.com> schrieb:[color=green]
>> I basically want to create an instance of a generic class where the
>> type T is not know at compile time.
>>
>> e.g.
>>
>> dim s as System.Type = GetMyType()
>> dim o as MyObj(Of s)[/color]
>
> \\\
> Dim GenericType As Type = GetType(List(Of ))
> Dim ParameterTypes( ) As Type = {GetType(Intege r)}
> Dim o As Object = _
> Activator.Creat eInstance( _
> GenericType.Mak eGenericType(Pa rameterTypes) _
> )
> ///
>
> --
> M S Herfried K. Wagner
> M V P <URL:http://dotnet.mvps.org/>
> V B <URL:http://classicvb.org/petition/>[/color]

[Herfried K. Wagner [MVP]]

Re: Use a System.Type in Generics?

"Cor Ligthert [MVP]" <notmyfirstname @planet.nl> schrieb:[color=blue]
> I am curious how I can use this Generic List of a typed class, while I
> don't know the members of the class?[/color]

The problem is that you can only do that using reflection because 'List(Of
X)' is not a 'List(Of )'. Thus I do not think that the solution I posted
makes much sense because generics are mainly a compile-time feature and the
compile-time advantages are lost when using reflection.

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://classicvb.org/petition/>