'ToString()' takes 1 arguments when DateTime?(Nullable) type I uses [duplicate]

问题

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No overload for method 'ToString" takes 1 arguments when casting date (3 answers)

Closed 3 years ago.

DateTime? NullableWhen I use DateTime? as Nullable type "ToString("dd MMMMyyyy " + "(HH:mm tt)")" error appears.

回答1:

You must use something like this. I've added null check as suggested by Colin

if(dateVariable.HasValue)
  string dateString = dateVariable.Value.ToString("dd MMMMyyyy " + "(HH:mm tt)");

Nullable<T> is a generc and it wraps object. You must access it via .Value property.

来源：https://stackoverflow.com/questions/39328689/tostring-takes-1-arguments-when-datetimenullable-type-i-uses