Text Validation Blip

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Text Validation, It's widely used but needs to be re-programmed by the developer. If using HandyControl we could do validation while the user types{in Xaml}, that will save some time.

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<hc: TextBox Validation="*&%" ValSpace=False />

now this Text Box will not allow to put { * , & , % } or Spaces , and will show a blip like this.

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I Tried doing it With tooltips, but it's not very convincing.

Additional context
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No file or test is named; start by reviewing HandyControl's WPF TextBox control and its XAML-facing properties, then compare the requested behavior with the existing tooltip approach. A complete result would define a validation syntax, reject configured characters or spaces while typing, and show the requested visual feedback.