Silverlight, WPF. How to determine is one control located over other?

What is the best solution to check is one control located over other.

For example, I have开发者_运维问答 two TextBoxes and when one TextBox is over the other I need to hide one of them.

AND i need to determine is this cotnrols overlaped before i will add them to visul tree!

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I assume you mean you want to find out if they overlap in the Z-dimension?

Untested:

// requires System.Windows.Controls.Toolkit.dll

using System.Windows.Controls.Primitives;
// ...

Rect? rect1 = myControl1.GetBoundsRelativeTo(someParentContainer);
Rect? rect2 = myControl2.GetBoundsRelativeTo(someParentContainer);

bool areIntersecting = rect1 != null && rect2 != null
    && rect1.Value.Intersect(rect2.Value) != Rect.Empty;

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If you're after a tool rather than a programmatic solution, snoop does this for WPF apps. It shows you a hierarchical view of the composition of controls in your app at runtime.

Never used it, but Silverlight Spy seems to be a Silverlight equivalent.