Re: Component constructor in .NET 2.0

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Edward Diener wrote:
Carl Daniel [VC++ MVP] wrote:
Edward Diener wrote:
I looked in the documentation for System.ComponentModel.Component's
constructor but I only noticed a constructor taking no parameters.
My understanding is that there is a second constructor which takes a
System.ComponentModel.IContainer interface object. Has this been the
case in previous .NET releases and has this changed with .NET 2.0 ?

Ildasm shows only the no-args constructor for V1.1 and V2.0. Why do
you believe there's another constructor?

If I use VS2005 to generate a component class, it creates both a no
argument constructor and a constructor which takes a
System.ComponentModel.IContainer container interface with the comment

"///
/// Required for Windows.Forms Class Composition Designer support
///"

This leads me to believe that all component derived classes need to
specify this second constructor. As a component developer I have added
this second constructor to all my components, with the appropriate
logic of adding the component to the container passed in the
constructor. Is this necessary ? What is the story with this second
constructor ? I could find no documentation regarding it in the
VS2005 doc for any .NET component classes.

IIUC, it has no function outside the windows forms designer - effectively an
internal implementation detail of the designer that leaks into your code.

-cd


.

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