Exception of type 'System.InvalidOperationException' occurred in mscorlib.ni.dll but was not handled

问题

I am getting this message:

"Exception of type 'System.InvalidOperationException' occurred in mscorlib.ni.dll but was not handled in user code"

This problem occurs when my TimePicker dont have any time choosen when I leave it empty.

My code for the TimePicker looks like this;

DateTime break1S = (DateTime)startBreak1.Value; 

Its on this row i am getting the message but if i set a time for the picker i dont get an message.

Any ideas?

**

回答1:

If startBreak1.Value is a string :

if (startBreak1!= null) 
    DateTime.TryParse(startBreak1.Value, out break1S);

if it's a Nullable<DateTime> (and I think it is)

DateTime break1S = startBreak1.HasValue 
                          ? startBreak1.Value
                          : new DateTime()//or anything you want;

or accept that break1S can be nullable :

var break1S = startBreak1;

回答2:

The solution look like this: 

DateTime break1S = startBreak1.Value.HasValue ? startBreak1.Value.Value : DateTime.MinValue;

回答3:

you can try this:

DateTime break1S = startBreak1.Value.HasValue ? startBreak1.Value.Value : DateTime.MinValue;

来源：https://stackoverflow.com/questions/16893855/exception-of-type-system-invalidoperationexception-occurred-in-mscorlib-ni-dll