[C# 4.0] 2. Dynamic (2)

核心提示： DynamicObject 和 ExpandoObject 都实现了 IDynamicMetaObjectProvider 接口，这是 DLR 进行动态操作所必须的，[C# 4.0] 2. Dynamic (2)(3)，publicclassDynamicObject:IDynamicMetaO

DynamicObject 和 ExpandoObject 都实现了 IDynamicMetaObjectProvider 接口，这是 DLR 进行动态操作所必须的。

public　class　DynamicObject　:　IDynamicMetaObjectProvider
{
　　//　Methods
　　protected　DynamicObject();
　　public　virtual　IEnumerable<string>　GetDynamicMemberNames();
　　public　virtual　DynamicMetaObject　GetMetaObject(Expression　parameter);
　　public　virtual　bool　TryBinaryOperation(BinaryOperationBinder　binder,　object　arg,　out　object　result);
　　public　virtual　bool　TryConvert(ConvertBinder　binder,　out　object　result);
　　public　virtual　bool　TryCreateInstance(CreateInstanceBinder　binder,　object[]　args,　out　object　result);
　　public　virtual　bool　TryDeleteIndex(DeleteIndexBinder　binder,　object[]　indexes);
　　public　virtual　bool　TryDeleteMember(DeleteMemberBinder　binder);
　　public　virtual　bool　TryGetIndex(GetIndexBinder　binder,　object[]　indexes,　out　object　result);
　　public　virtual　bool　TryGetMember(GetMemberBinder　binder,　out　object　result);
　　public　virtual　bool　TryInvoke(InvokeBinder　binder,　object[]　args,　out　object　result);
　　public　virtual　bool　TryInvokeMember(InvokeMemberBinder　binder,　object[]　args,　out　object　result);
　　public　virtual　bool　TrySetIndex(SetIndexBinder　binder,　object[]　indexes,　object　value);
　　public　virtual　bool　TrySetMember(SetMemberBinder　binder,　object　value);
　　public　virtual　bool　TryUnaryOperation(UnaryOperationBinder　binder,　out　object　result);
}
　
public　sealed　class　ExpandoObject　:　IDynamicMetaObjectProvider,　IDictionary<string,　object>,　
　　ICollection<KeyValuePair<string,　object>>,　IEnumerable<KeyValuePair<string,　object>>,　
　　IEnumerable,　INotifyPropertyChanged
{
　　//　Events
　　event　PropertyChangedEventHandler　INotifyPropertyChanged.PropertyChanged;
　　//　Methods
　　public　ExpandoObject();
　　void　ICollection<KeyValuePair<string,　object>>.Add(KeyValuePair<string,　object>　item);
　　void　ICollection<KeyValuePair<string,　object>>.Clear();
　　bool　ICollection<KeyValuePair<string,　object>>.Contains(KeyValuePair<string,　object>　item);
　　void　ICollection<KeyValuePair<string,　object>>.CopyTo(KeyValuePair<string,　object>[]　array,　int　arrayIndex);
　　bool　ICollection<KeyValuePair<string,　object>>.Remove(KeyValuePair<string,　object>　item);
　　void　IDictionary<string,　object>.Add(string　key,　object　value);
　　bool　IDictionary<string,　object>.ContainsKey(string　key);
　　bool　IDictionary<string,　object>.Remove(string　key);
　　bool　IDictionary<string,　object>.TryGetValue(string　key,　out　object　value);
　　IEnumerator<KeyValuePair<string,　object>>　IEnumerable<KeyValuePair<string,　object>>.GetEnumerator();
　　IEnumerator　IEnumerable.GetEnumerator();
　　
　　DynamicMetaObject　IDynamicMetaObjectProvider.GetMetaObject(Expression　parameter);
　　//　Properties
　　int　ICollection<KeyValuePair<string,　object>>.Count　{　get;　}
　　bool　ICollection<KeyValuePair<string,　object>>.IsReadOnly　{　get;　}
　　object　IDictionary<string,　object>.this[string　key]　{　get;　set;　}
　　ICollection<string>　IDictionary<string,　object>.Keys　{　get;　}
　　ICollection<object>　IDictionary<string,　object>.Values　{　get;　}
}

DynamicObject 集中实现成员调用，可以更灵活地调度。而 ExpandoObject 则更轻便，更接近于动态语言编程习惯。