如何通过C#1.x实现quot？
//本文参阅 CSDN ccat 的 MarchLibrary 修改 // C# 1.x 实现 "强类型元素唯一的 ArrayList"
using System; using System.Collections; /// 任何元素的 Type 都应当等于指定的类型或为指定类型的子类。 /// 对于值类型,最好先行装箱再使用。 /// 作为 C# 1.x 语言实现泛型功能之前的代用品(运行时错误)。 //方法1: 通过继承于 System.Collections.ArrayList 实现 public class StrongTypeUniqueArrayList : ArrayList { private Type _type; /// <summary> /// 禁止默认构造。 /// </summary> private StrongTypeUniqueArrayList() { } /// <summary> /// 在容器初始化时指定其元素类型 /// </summary> /// <param name="ElementType">ArrayList (元素)类型</param> public StrongTypeUniqueArrayList(System.Type ElementType) { _type = ElementType; } /// <summary> /// 不能再更改其内部元素类型。 /// </summary> public Type Type { get { return _type; } } private bool IsMatchType(Type eType) { return (eType == _type)|(eType.IsSubclassOf(_type)); }public override object this[int index] { set { if (IsMatchType(value.GetType())) { if (base.Contains(value)) { if (base.IndexOf(value) == index) { base[index] = value; } else { throw new ArgumentException(value.ToString() + " 元素重复","value"); } } else { base[index] = value; } } else { throw new ArgumentException(value.GetType().FullName + " 类型错误", "value"); } } }
public override int Add(object value)
{ if (!base.Contains(value) && IsMatchType(value.GetType())) { base.Add(value); return 1; } else { throw new ArgumentException(value.GetType().FullName + " 类型错误 或 " + value.ToString() + " 元素重复", "value"); //return -1; } } public override void Insert(int index, object value) { if (!base.Contains(value) && IsMatchType(value.GetType())) { base.Insert(index,value); } else { throw new ArgumentException(value.GetType().FullName + " 类型错误 或 " + value.ToString() + " 元素重复", "value"); } }public override void InsertRange(int index, ICollection c)
{ System.Collections.IEnumerator ie = c.GetEnumerator(); while (ie.MoveNext()) { if (base.Contains(ie.Current) || !IsMatchType(ie.Current.GetType())) { throw new ArgumentException(ie.Current.GetType().FullName + " 类型错误 或 " + ie.Current.ToString() + " 元素重复", "c"); } } base.InsertRange(index,c); } public override void SetRange(int index, ICollection c) { System.Collections.IEnumerator ie = c.GetEnumerator(); int i = 0; while (ie.MoveNext()) { if (IsMatchType(ie.Current.GetType())) { if (base.Contains(ie.Current) && base.IndexOf(ie.Current) != i) { throw new ArgumentException(ie.Current.ToString() + " 元素重复","c"); } } else { throw new ArgumentException(ie.Current.GetType().FullName + " 类型错误", "c"); } i++; } base.SetRange(index,c); } public override void AddRange(ICollection c) { System.Collections.IEnumerator ie = c.GetEnumerator(); while (ie.MoveNext()) { if (base.Contains(ie.Current) || !IsMatchType(ie.Current.GetType())) { throw new ArgumentException(ie.Current.GetType().FullName + " 类型错误 或 " + ie.Current.ToString() + " 元素重复", "c"); } } base.AddRange(c); } } //Test: public class Class1 { private static int i = 0; public string xxx = "test"; public Class1() { System.Console.WriteLine(i++); } static void Main(string[] args) { System.Console.WriteLine("Hello World"); Class1 c1 = new Class1(); Class1 c2 = new Class1(); Class1 c3 = new Class1(); Class1 c4 = new Class1(); //StrongTypeUniqueArrayList x = new StrongTypeUniqueArrayList(typeof(Class1)); StrongTypeUniqueArrayList x = new StrongTypeUniqueArrayList(System.Type.GetType("Class1")); System.Console.WriteLine(x.Type); x.Add(c1); x.Add(c2); x.Add(c3); x.Insert(0,c4); //x.Add(new Class1()); //x.Add(c1); //x[2]= new Object(); //x.Insert(2,new Object()); //类型错误 //x.Insert(2,c2); //x.Add(c2); //元素重复 } }//方法2: 不通过继承于 System.Collections.ArrayList 实现 //《Refactoring: Improving the Design of Existing Code》 // 3.21 Refused Bequest: Replace Inheritancewith Delegation
using System; using System.Collections; public class Class1 { private static int i = 0; public string xxx = "test"; public Class1() { System.Console.WriteLine(i++); xxx = i.ToString(); } public override string ToString() { return xxx; } static void Main(string[] args) { System.Console.WriteLine("Hello World"); System.Console.WriteLine("Hello World"); Class1 c1 = new Class1(); Class1 c2 = new Class1(); Class1 c3 = new Class1(); Class1 c4 = new Class1(); StrongTypeUniqueArrayList x = new StrongTypeUniqueArrayList(System.Type.GetType("Class1")); System.Console.WriteLine(x.Type); x.Add(c1); x.Add(c2); x.Add(c3); x.Insert(0,c4); System.Collections.IEnumerator ie = x.GetEnumerator(); while (ie.MoveNext()) System.Console.WriteLine(ie.Current.ToString()); x[0]= c4 ; while (ie.MoveNext()) System.Console.WriteLine(ie.Current.ToString()); x.Reset(); foreach(Object o in x) System.Console.WriteLine(o.ToString() + "each"); } }
public class StrongTypeUniqueArrayList : System.Collections.IEnumerator//,System.Collections.IEnumerable // 支持 foreach { private ArrayList al; private Type _type; private int _index = -1;
public StrongTypeUniqueArrayList(System.Type ElementType) { al = new ArrayList(); _type = ElementType; }
public System.Collections.IEnumerator GetEnumerator() // 支持 迭代 和 foreach { return this; }
public bool MoveNext() // 支持 foreach { return ++ _index < al.Count; } public void Reset() // 支持 foreach { _index = -1; } public Object Current // 支持 foreach { get { return al[_index]; } }
public Type Type { get { return _type; } } private bool IsMatchType(Type eType) { return (eType == _type)|(eType.IsSubclassOf(_type)); } public object this[int index] { set { if (IsMatchType(value.GetType())) { if (al.Contains(value)) { if (al.IndexOf(value) == index) { al[index] = value; } else { throw new ArgumentException(value.ToString() + " 元素重复","value"); } } else { al[index] = value; } } else { throw new ArgumentException(value.GetType().FullName + " 类型错误", "value"); } } get { return al[index]; } } public int Add(object value) { if (!al.Contains(value) && IsMatchType(value.GetType())) { al.Add(value); return 1; } else { throw new ArgumentException(value.GetType().FullName + " 类型错误 或 " + value.ToString() + " 元素重复", "value"); } } public void Insert(int index, object value) { if (!al.Contains(value) && IsMatchType(value.GetType())) { al.Insert(index,value); } else { throw new ArgumentException(value.GetType().FullName + " 类型错误 或 " + value.ToString() + " 元素重复", "value"); } } public void InsertRange(int index, ICollection c) { System.Collections.IEnumerator ie = c.GetEnumerator(); while (ie.MoveNext()) { if (al.Contains(ie.Current) || !IsMatchType(ie.Current.GetType())) { throw new ArgumentException(ie.Current.GetType().FullName + " 类型错误 或 " + ie.Current.ToString() + " 元素重复", "c"); } } al.InsertRange(index,c); } public void SetRange(int index, ICollection c) { System.Collections.IEnumerator ie = c.GetEnumerator(); int i = 0; while (ie.MoveNext()) { if (IsMatchType(ie.Current.GetType())) { if (al.Contains(ie.Current) && al.IndexOf(ie.Current) != i) { throw new ArgumentException(ie.Current.ToString() + " 元素重复","c"); } } else { throw new ArgumentException(ie.Current.GetType().FullName + " 类型错误", "c"); } i++; } al.SetRange(index,c); } public void AddRange(ICollection c) { foreach(Object o in al) { if (al.Contains(o) || !IsMatchType(o.GetType())) { throw new ArgumentException(o.GetType().FullName + " 类型错误 或 " + o.ToString() + " 元素重复", "c"); } } al.AddRange(c); } }