获取可空类型的类型定义会破坏不可空类型的代码

Question

如果您想查看，这是对以下问题的后续问题：Parse to Nullable Enum

Type t = currentProperty.PropertyType;
if (t.GetGenericTypeDefinition() == typeof(Nullable<>))
    t = t.GetGenericArguments().First();

我在第 2 行遇到错误，即 IF 语句。

System.Reflection.TargetInvocationException : Exception has been thrown by the 
target of an invocation. ----> System.InvalidOperationException : This operation 
is only valid on generic types.
at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
at System.Reflection.RuntimeConstructorInfo.Invoke(BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at System.RuntimeType.CreateInstanceImpl(BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
at System.Activator.CreateInstance(Type type, Object[] args)

如何在执行 IF 语句中的代码之前测试该条件？

Answer 1

Here is the MSDN documentation on checking for nullable types

看来您需要添加以下内容：

if(t.IsGenericType && ...