You will find a validation topic in the documentation for any control that validation is a relevant topic. You can search the documentation for "Validation"; if you are not sure what you're looking for just yet
Note: this is not the same thing you might be used to using in other frameworks like WPF. Xamarin.Forms and MAUI XAML is very different and doesn't have the same mechanisms. To learn more you can google/Bing "Validation in Xamarin.Forms" (.NET MAUI doesn't have many resources available, so you want to use "Xamarin.Forms" as a search term until MAUI has more content available.. even the official Microsoft documentation is very small because they are not done building it)
Lance | Manager Technical Support
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