Our RadGridView control supports two validation levels - cell level and row level validation. We do not do automatic data validation through the IDataErrorInfo interface yet, but we will be supporting it in the future.
For now you can implement your validation method in your business object, then declare a validation event handler where you can call your validation method.
I made a simple example for your implementing cell level validation.
Greetings,
Atanas
the Telerik team
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