c# - Unable to cast object of type 'System.DateTime' to type 'System.String' -

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getting error has me stumped. i'm assuming it's simple can't seem figure 1 out, code causing error:

if ((string) _nullabledatetimepicker1.value != string.empty && _nullabledatetimepicker1.value != null) {      _nullabledatetimepicker1.value = null; }

when clicking on search button in windows form, popping up:

unable cast object of type 'system.datetime' type 'system.string'.

it appears type of nullable-type instance of _nullabledatetimepicker1 datetime, not string; need compare datetime or convert string.

so, in simplest sense:

_nullabledatetimepicker1.value.tostring() != string.empty

however, beware danger of not checking hasvalue, cause nullreferenceexception if value null; so, check little backwards.

and then, if wasn't null, you'd have datetime.minvalue, , tostring wouldn't return empty string. therefore, check null on nullable thing, , if not null, compare datetime.minvalue (unless there's quirk in code means have different 'default'.


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