Just thought I would add a note because I have not been able to see this behaviour documented elsewhere.
When using
<
telerik:RadMaskedTextInput
Mask
=
""
TextMode
=
"PlainText"
/>
adding the text a_b changes to ab when navigated away from. The fix is to use MaskedText as the textmode instead which is the default so it would be
<
telerik:RadMaskedTextInput
Mask
=
""
TextMode
=
"MaskedText"
/>
or simply
<
telerik:RadMaskedTextInput
Mask
=
""
/>
Hope this helps anyone else with the same issue