RadDateTimeInput uses a DateTime type as value and not TimeSpan. So, if you need to use TimeSpan as a Value of the MaskedInputControl you should use:
- RadMaskedTextInpud with custom mask token which takes only digits - you can see how to write this in our help topic - Mask Tokens
. In your case your valid characters would be only digits and the mask would be "$$:$$:$$" to have ":" symbols between the numbers;
- use a ViewModel and custom validation rule to restrict the user input per your requirement. More about validations you can find here
Please take a look at this topics and write us back if you need any further assistance.
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