检查属性是类型还是可空类型

Question

I am currently checking if a property type is either a DateTime or a nullable DateTime like this:

if (prop.PropertyType == typeof(DateTime) || prop.PropertyType == typeof(DateTime?))

Can anyone please tell me if I can somehow condense this into a single statement by checking the underlying type?

Answer 1

Here is a simple sollution: typeof(DateTime?).IsAssignableFrom(prop.PropertyType) . This will be true for DateTime? or DateTime and false for others.

Answer 2

You may try this:

if (prop.PropertyType.UnderlyingSystemType==typeof(DateTime))

...

Answer 3

Try something like this

public class Program
{
    public static void Main(string[] args)
    {
        //Your code goes here
         DateTime? nullableDate = null;

         bool output = CheckNull.IsNullable(nullableDate); // false

         Console.WriteLine(output );
    }

 public static class CheckNull
 {
   public static bool IsNullable<T>(T t) { return false; }
   public static bool IsNullable<T>(T? t) where T : struct { return true; }
 }
}

output : True