System.ComponentModel.ReflectTypeDescriptionProvider.ReflectedTypeData.GetAttributes C# (CSharp) 메소드

GetAttributes() 개인적인 메소드

Retrieves custom attributes.
private GetAttributes ( ) : AttributeCollection
리턴 AttributeCollection
            internal AttributeCollection GetAttributes()
            {
                // Worst case collision scenario:  we don't want the perf hit
                // of taking a lock, so if we collide we will query for
                // attributes twice.  Not a big deal.
                //
                if (_attributes == null)
                {
                    // Obtaining attributes follows a very critical order: we must take care that
                    // we merge attributes the right way.  Consider this:
                    //
                    // [A4]
                    // interface IBase;
                    //
                    // [A3]
                    // interface IDerived;
                    //
                    // [A2]
                    // class Base : IBase;
                    //
                    // [A1]
                    // class Derived : Base, IDerived
                    //
                    // Calling GetAttributes on type Derived must merge attributes in the following
                    // order:  A1 - A4.  Interfaces always lose to types, and interfaces and types
                    // must be merged in the same order.  At the same time, we must be careful
                    // that we don't always go through reflection here, because someone could have
                    // created a custom provider for a type.  Because there is only one instance
                    // of ReflectTypeDescriptionProvider created for typeof(object), if our code
                    // is invoked here we can be sure that there is no custom provider for
                    // _type all the way up the base class chain.
                    // We cannot be sure that there is no custom provider for
                    // interfaces that _type implements, however, because they are not derived
                    // from _type.  So, for interfaces, we must go through TypeDescriptor
                    // again to get the interfaces attributes.  

                    // Get the type's attributes. This does not recurse up the base class chain.
                    // We append base class attributes to this array so when walking we will
                    // walk from Length - 1 to zero.
                    //
                    Attribute[] attrArray = ReflectTypeDescriptionProvider.ReflectGetAttributes(_type);
                    Type baseType = _type.GetTypeInfo().BaseType;

                    while (baseType != null && baseType != typeof(object))
                    {
                        Attribute[] baseArray = ReflectTypeDescriptionProvider.ReflectGetAttributes(baseType);
                        Attribute[] temp = new Attribute[attrArray.Length + baseArray.Length];
                        Array.Copy(attrArray, 0, temp, 0, attrArray.Length);
                        Array.Copy(baseArray, 0, temp, attrArray.Length, baseArray.Length);
                        attrArray = temp;
                        baseType = baseType.GetTypeInfo().BaseType;
                    }

                    // Next, walk the type's interfaces.  We append these to
                    // the attribute array as well.
                    //
                    int ifaceStartIdx = attrArray.Length;
                    Type[] interfaces = _type.GetTypeInfo().GetInterfaces();
                    for (int idx = 0; idx < interfaces.Length; idx++)
                    {
                        Type iface = interfaces[idx];

                        // only do this for public interfaces.
                        //
                        if ((iface.GetTypeInfo().Attributes & (TypeAttributes.Public | TypeAttributes.NestedPublic)) != 0)
                        {
                            // No need to pass an instance into GetTypeDescriptor here because, if someone provided a custom
                            // provider based on object, it already would have hit.
                            AttributeCollection ifaceAttrs = TypeDescriptor.GetAttributes(iface);
                            if (ifaceAttrs.Count > 0)
                            {
                                Attribute[] temp = new Attribute[attrArray.Length + ifaceAttrs.Count];
                                Array.Copy(attrArray, 0, temp, 0, attrArray.Length);
                                ifaceAttrs.CopyTo(temp, attrArray.Length);
                                attrArray = temp;
                            }
                        }
                    }

                    // Finally, put all these attributes in a dictionary and filter out the duplicates.
                    //
                    OrderedDictionary attrDictionary = new OrderedDictionary(attrArray.Length);

                    for (int idx = 0; idx < attrArray.Length; idx++)
                    {
                        bool addAttr = true;
                        if (idx >= ifaceStartIdx)
                        {
                            for (int ifaceSkipIdx = 0; ifaceSkipIdx < s_skipInterfaceAttributeList.Length; ifaceSkipIdx++)
                            {
                                if (s_skipInterfaceAttributeList[ifaceSkipIdx].GetTypeInfo().IsInstanceOfType(attrArray[idx]))
                                {
                                    addAttr = false;
                                    break;
                                }
                            }
                        }

                        if (addAttr && !attrDictionary.Contains(attrArray[idx].TypeId))
                        {
                            attrDictionary[attrArray[idx].TypeId] = attrArray[idx];
                        }
                    }

                    attrArray = new Attribute[attrDictionary.Count];
                    attrDictionary.Values.CopyTo(attrArray, 0);
                    _attributes = new AttributeCollection(attrArray);
                }

                return _attributes;
            }