to change the text of the notification via its client-side API
Please also note that the Text property takes an HTML string, so new lines should be <br /> instead of \r\n. Also calling the same method many times will not result in many notifications being shown, but one with the last text you provide, so I suggest you have your method built up the errors/messages you need to show (by appending them to a string) and then only once set it to the Text of the notification and call its Show() method.
All the best,
the Telerik team
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