With custom DateTime Format, the DateTimePicker shows no reaction on clicking the spin buttons or pressing the Up-/Down keys. The manual entry of a value gets lost when the control loses focus, as reported in Issue 18624, (which was already fixed, but obviously for default format only).
__If additionaly, the Custom Format string is not set, the whole application crashes on any attempt to spin the value!__
Comments: ** Comment from web user: emartin **
__If additionaly, the Custom Format string is not set, the whole application crashes on any attempt to spin the value!__
Comments: ** Comment from web user: emartin **
Using the v1.9 sample application, I have successfully tested the following various custom format string scenarios:
yy-MMMM-dd
dd MMMM yyyy hh:mm
yyyy () MM () dd
yy*dd h:tt
Unfortunately, beside the issues mentioned below, I could not reproduce your problem
Can you provide me with a more details about how to reproduce and the resulting undesired behavior ?
Concerning the crash, it is already fixed for the next version.
Theses issues are expected to be fixed in version 2.0:
[Issue 19312](http://wpftoolkit.codeplex.com/workitem/19312)
[Issue 19040](http://wpftoolkit.codeplex.com/workitem/19040)