构建可反转排序的泛型字典类(8)--实现IDictionary接口

 

8. 实现IDictionary<TKey, TValue>接口

由于前面实现了IDictionary接口，现在实现IDictionary<TKey, TValue>也就没什么困难的了，照葫芦画瓢。

首先改变类声明：

public   class  ReversibleSortedList < TKey, TValue >  :IDictionary < TKey, TValue >
    IDictionary, IEnumerable < KeyValuePair < TKey, TValue >> , ICollection,
IEnumerable, ICollection < KeyValuePair < TKey, TValue >>

 

然后实现ICollection<KeyValuePair<TKey, TValue>>接口成员：

bool  ICollection < KeyValuePair < TKey, TValue >> .IsReadOnly
    {
         get
        {
             return   false ;
        }
    }
     void  ICollection < KeyValuePair < TKey, TValue >> .Add(
        KeyValuePair < TKey, TValue >  keyValuePair)
    {
         this .Add(keyValuePair.Key, keyValuePair.Value);
    }
     bool  ICollection < KeyValuePair < TKey, TValue >> .Contains(
        KeyValuePair < TKey, TValue >  keyValuePair)
    {
         int  num1  =   this .IndexOfKey(keyValuePair.Key);
         if  ((num1  >=   0 )  &&  EqualityComparer < TValue > .Default.Equals( this .values[num1],
            keyValuePair.Value))
        {
             return   true ;
        }
         return   false ;
    }
     void  ICollection < KeyValuePair < TKey, TValue >> .CopyTo(
        KeyValuePair < TKey, TValue > [] array,  int  arrayIndex)
    {
         if  (array  ==   null )
        {
             throw   new  ArgumentNullException( " array " );
        }
         if  ((arrayIndex  <   0 )  ||  (arrayIndex  >  array.Length))
        {
             throw   new  ArgumentOutOfRangeException(
                   " arrayIndex " ,  " Need a non-negative number " );
        }
         if  ((array.Length  -  arrayIndex)  <   this .Count)
        {
             throw   new  ArgumentException( " ArrayPlusOffTooSmall " );
        }
         for  ( int  num1  =   0 ; num1  <   this .Count; num1 ++ )
        {
            KeyValuePair < TKey, TValue >  pair1;
            pair1  =   new  KeyValuePair < TKey, TValue > (
                         this .keys[num1],  this .values[num1]);
            array[arrayIndex  +  num1]  =  pair1;
        }
    }
     bool  ICollection < KeyValuePair < TKey, TValue >> .Remove(
        KeyValuePair < TKey, TValue >  keyValuePair)
    {
         int  num1  =   this .IndexOfKey(keyValuePair.Key);
         if  ((num1  >=   0 )  &&  EqualityComparer < TValue > .Default.Equals(
             this .values[num1], keyValuePair.Value))
        {
             this .RemoveAt(num1);
             return   true ;
        }
         return   false ;
}

 

需要注意，Count属性和Clear方法都是共用方法，不需要再次实现。

接下来实现IDictionary<TKey, TValue>接口，它是最主要的接口，所有成员均为公有的，前面我们已经实现了Add、ContainsKey方法，这里不再列出：

    ICollection < TKey >  IDictionary < TKey, TValue > .Keys
    {
         get
        {
             return   this .GetKeyListHelper();
        }
    }
    ICollection < TValue >  IDictionary < TKey, TValue > .Values
    {
         get
        {
             return   this .GetValueListHelper();
        }
    }
     public  TValue  this [TKey key]  // Item属性，就是索引器
    {   
         get
        {
            TValue local1;
             int  num1  =   this .IndexOfKey(key);
             if  (num1  >=   0 )
            {
                 return   this .values[num1];
            }
             else
            {
                local1  =   default (TValue);
                 return  local1;
            }
        }
         set
        {
             if  (key  ==   null )
            {
                 throw   new  ArgumentNullException( " key " );
            }
             int  num1  =  Array.BinarySearch < TKey > ( this .keys,  0 ,  this ._size, key,
                 this ._sortDirectionComparer);
             if  (num1  >=   0 )
            {
                 this .values[num1]  =  value;
                 this .version ++ ;
            }
             else
            {
                 this .Insert( ~ num1, key, value);
            }
        }
    }
     public   bool  Remove(TKey key)
    {
         int  num1  =   this .IndexOfKey(key);
         if  (num1  >=   0 )
        {
             this .RemoveAt(num1);
        }
         return  (num1  >=   0 );
    }
     public   bool  TryGetValue(TKey key,  out  TValue value)
    {
         int  num1  =   this .IndexOfKey(key);
         if  (num1  >=   0 )
        {
            value  =   this .values[num1];
             return   true ;
        }
        value  =   default (TValue);
         return   false ;
    }

 

另外需要添加一个RemoveAt方法：

     // 移除指定索引元素
     public   void  RemoveAt( int  index)
    {
         if  ((index  <   0 )  ||  (index  >=   this ._size))
        {
             throw   new  ArgumentOutOfRangeException( " index " ,  " Index out of range " );
        }
         this ._size -- ;
         if  (index  <   this ._size)
        {
            Array.Copy( this .keys, ( int )(index  +   1 ),  this .keys, index,
                        ( int )( this ._size  -  index));
            Array.Copy( this .values, ( int )(index  +   1 ),  this .values, index,
                        ( int )( this ._size  -  index));
        }
         this .keys[ this ._size]  =   default (TKey);
         this .values[ this ._size]  =   default (TValue);
         this .version ++ ;
    }

 

最后，进行测试，这一次不再使用int做为键，而改用string：

static   void  Main()
    {
        ReversibleSortedList < string ,  string >  rs  =   new  ReversibleSortedList < string ,  string > ();
         // 添加元素
        rs.Add( " 3 " ,  " a " );
        rs.Add( " 1 " ,  " b " );
        rs.Add( " 2 " ,  " c " );
        rs.Add( " 6 " ,  " d " );
        rs.Add( " 5 " ,  " e " );
        rs.Add( " 4 " ,  " f " );
         // 使用DictionaryEntry打印键/值
         foreach  (KeyValuePair < string ,  string >  d  in  rs)
        {
            Console.WriteLine(d.Key  +   "      "   +  d.Value);
        }
        Console.WriteLine( " 删除索引为“2”的“5”的元素 " );
        rs.Remove( " 2 " );
        rs.Remove( " 5 " );
         foreach  (KeyValuePair < string ,  string >  d  in  rs)
        {
            Console.WriteLine(d.Key  +   "      "   +  d.Value);
        }
}

 

ReversibleSortedList 0.7版本：实现IDictionary<TKey, TValue>接口

完整代码下载

运行结果：

1   b

2   c

3   a

4   f

5   e

6   d

删除索引为“2”的“5”的元素

1   b

3   a

4   f

6   d