如何从 UnaryExpression 获取类型？

Question

我有一个属性定义为 Expression<Func<Kitten, object>> 即 c => c.KittenAge，其中 KittenAge 是一个 int?

我想得到这个的类型

我的代码是：

Expression<Func<Kitten, object>> property = c => c.KittenAge;

var unaryExpression = property.Body as UnaryExpression;

if (Nullable.GetUnderlyingType(unaryExpression.Type) == null)
{
   // Error, must be nullable
}

不幸的是，错误行总是被命中，因为 Type 是 System.Object。如何从表达式中获取 int? 的类型？

Answer 1

试试这个：

    Expression<Func<Kitten, object>> property = c => c.KittenAge;
    var unaryExpression = property.Body as UnaryExpression;
    var propertyExpression = unaryExpression.Operand as MemberExpression;

    if (Nullable.GetUnderlyingType(propertyExpression.Type) == null)
    {
      // Error, must be nullable
    }

如何从 UnaryExpression 获取类型？

How can I get the Type from a UnaryExpression?

c#

reflection

lambda

expression-trees