通过一元表达式访问对象属性值

Question

如何在不使用“直接”反射的情况下，通过匹配一元表达式“成员名称”来获取对象属性值？

public object DoSomething<T>(UnaryExpression uExp, T obj)
   {            
        object res = null;                       
        // NOTE: UnaryExpression contains a property from T type.
        // TODO: get UnaryExpressionMatchingProperty value

        // res = obj.UnaryExpressionMatchingProperty;
        return res;
    }

- Dryadwoods

---

uExp.Operand as MemberExpression，然后获取成员细节？ - Jim

Answer 1

这应该生成值或者null，如果一元表达式的结构不符合预期：

var prop = ((uExp.Operand as MemberExpression)?.Member as PropertyInfo);
if (prop?.CanRead == true) { // Needs "== true" because ?. makes Nullable<bool>
    res = prop.GetValue(obj);
}

- Sergey Kalinichenko