I have a C# WPF project which generates daily and weekly reports automatically. I want to inform the user when new reports are available, so I thought of a badge like on the
Use a Border element and place your text within it. You can set the CornerRadius property for the Border appropriately so that it looks like a circle (or a rounded-rectangle shape, in case the number is bigger).
Here's a first cut, which exploits the fact that CornerRadius will get clamped to half the height or width in Y and X respectively:
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