如何通过反射区分值类型,可空值类型,枚举,可空枚举,引用类型？

Question

如何通过反射区分值类型,可空值类型,枚举,可空枚举,引用类型？

enum MyEnum
    {
        One,
        Two,
        Three
    }

    class MyClass
    {
        public int IntegerProp { get; set; }
        public int? NullableIntegerProp { get; set; }
        public MyEnum EnumProp { get; set; }
        public MyEnum? NullableEnumProp { get; set; }
        public MyClass ReferenceProp { get; set; }
    }

    class Program
    {
        static void Main(string[] args)
        {   
            Type classType = typeof(MyClass);

            PropertyInfo propInfoOne = classType.GetProperty("IntegerProp");
            PropertyInfo propInfoTwo = classType.GetProperty("NullableIntegerProp");
            PropertyInfo propInfoThree = classType.GetProperty("EnumProp");
            PropertyInfo propInfoFour = classType.GetProperty("NullableEnumProp");
            PropertyInfo propInfoFive = classType.GetProperty("ReferenceProp");

            propInfoOne.???
            ...............
            ...............
        }
    }

在propInfo中,哪些信息可以被检索？

Answer 1

以下是检查enum,nullable,primitve和value类型的方法;

Console.WriteLine(propInfoOne.PropertyType.IsPrimitive); //true
Console.WriteLine(propInfoOne.PropertyType.IsValueType); //false, value types are structs

Console.WriteLine(propInfoThree.PropertyType.IsEnum); //true

var nullableType = typeof (Nullable<>).MakeGenericType(propInfoThree.PropertyType);
Console.WriteLine(nullableType.IsAssignableFrom(propInfoThree.PropertyType)); //true

请注意,值类型和基元是不同的东西.基元只是映射到类型的shorthands(例如bool> System.Boolean).值类型按值传递; 它们是struct(ure)而不是类.