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Refer to Silverlight Control by name or tag in C#

I have a couple of controls that I created in c# -- they are not declared in XAML. I am looking for a way to refer to these controls programatically.

for instance, I create a rectangle and assign a few properties including the name and tag attributes:
Rectangle myRectangle = new Rectangle();
myRectangle.Name = "rec1";
myRectangle.Tag = "tagRec1";
myCanvas.Children.Add(myRectangle);

I create several rectangles and want to be able to refer to them later on in code. However, I get an error trying to refer to them as I would an object declared in XAML.
rec1.Opacity for example.
The error is 'the name 'rec1' does not exist in the current context'

How do I refer to these objects once they are created?

ASKER CERTIFIED SOLUTION

mikebirt

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EDDYKT

have you tried

Rectangle t = (Rectangle)this.FindName("rec1");

mikebirt

Hi,

Good idea EDDYKT! that got me thinking... you can't use the FindName still, you have to call RegisterName first. Then you can use FindName

HTH

Mike

            string rectangleName = "rec";
            Rectangle r = new Rectangle();
            r.Name = rectangleName;

            myCanvas.Children.Add(r);

            this.RegisterName(rectangleName, r);

            Rectangle rAgain = (Rectangle)FindName(rectangleName);

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VoodooFrog

ASKER

thank you -- this is a home project, so I will try these things tonight after work. It looks like that is the solution that I am looking for though. -- registering the name looks like it will do that.

mikebirt

Hi,

If you register the name you can use EDDYKT's idea of FindName, but you still can't use the 'this' instance to reference it directly. In my previous code example, this.rec wouldn't work, you must use FindName("rec").

HTH

Mike

VoodooFrog

ASKER

I am getting a failure on the registering the rectangle name. Says that the 'SLapp1 does not contain a definition for 'RegisterName'

In looking up the reference to RegisterName is says that the Namespace is System.Windows which is already incuded in the project.

VoodooFrog

ASKER

the dictionary seems to be the simplest way reall -- registerName doesn't seem to work for some reason.

EDDYKT

don't think you need to register name,

just do

Rectangle t = (Rectangle)this.FindName("rec1");