IterateContext.cs :  » Persistence-Frameworks » iBATIS.NET » IBatisNet » DataMapper » Configuration » Sql » Dynamic » Handlers » C# / CSharp Open Source

#region Apache Notice
/*****************************************************************************
 * $Header: $
 * $Revision: 408164 $
 * $Date: 2006-05-21 14:27:09 +0200 (dim., 21 mai 2006) $
 * 
 * iBATIS.NET Data Mapper
 * Copyright (C) 2004 - Gilles Bayon
 *  
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 ********************************************************************************/
#endregion

#region Imports
using System;
using System.Collections;

using IBatisNet.DataMapper.Exceptions;
#endregion

namespace IBatisNet.DataMapper.Configuration.Sql.Dynamic.Handlers{
  /// <summary>
  /// Summary description for IterateContext.
  /// http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dncscol/html/csharp01212002.asp
  /// http://www.microsoft.com/mspress/books/sampchap/6173.asp
  /// http://www.dur.ac.uk/barry.cornelius/java/a.taste.of.csharp/onefile/
  /// </summary>
  public sealed class IterateContext : IEnumerator
  {
    #region Fields
    private ICollection _collection;
    private ArrayList _items = new ArrayList();
    int _index = -1;
    #endregion


    /// <summary>
    /// Constructor
    /// </summary>
    /// <param name="collection"></param>
    public IterateContext(object collection)
    {
       if (collection is ICollection) 
       {
        _collection = (ICollection)collection;
       } 
       else if (collection.GetType().IsArray) 
       {
        object[] array = (object[])collection;
        ArrayList list = new ArrayList();
        int lenght = array.Length;
        for(int i=0;i<lenght;i++)
        {
          list.Add(array[i]);
        }
        _collection = (ICollection)list;
      } 
      else 
      {
        throw new DataMapperException("ParameterObject or property was not a Collection, Array or Iterator.");
      }

      IEnumerable enumerable = (IEnumerable)collection;
      IEnumerator enumerator = enumerable.GetEnumerator();

      while (enumerator.MoveNext() != false)
      {
        _items.Add(enumerator.Current);
      }
      IDisposable disposable = enumerator as IDisposable;
      if (disposable != null)
      {
        disposable.Dispose();
      }
      _index = -1;
    }

    /// <summary>
    /// Sets the enumerator to its initial position,
    ///  which is before the first element in the collection.
    /// </summary>
    public void Reset()
    {
      _index = -1;
    }

    /// <summary>
    /// Advances the enumerator to the next element of the collection.
    /// </summary>
    /// <returns>
    /// True if the enumerator was successfully advanced to the next element;
    /// False if the enumerator has passed the end of the collection.
    ///</returns>
    public bool MoveNext()
    {
      _index++;
      if (_index == _items.Count)
        return false;

      return true;
    }

    /// <summary>
    /// Gets the current element in the collection.
    /// </summary>
    public object Current
    {
      get
      {
        return _items[_index];
      }
    }

    /// <summary>
    /// Gets the index of the current element in the collection.
    /// </summary>
    public int Index
    {
      get
      {
        return _index;
      }
    }

    /// <summary>
    /// Return true if the current element is the first.
    /// </summary>
    public bool IsFirst
    {
      get
      {
        return (_index == 0);
      }
    }

    /// <summary>
    ///  Return true if the current element is the last.
    /// </summary>
    public bool IsLast
    {
      get
      {
        return (_index == (_items.Count-1));
      }
    }

    /// <summary>
    /// Removes from the underlying collection the last element returned by the iterator. 
    /// </summary>
    public void Remove() 
    {
      if (_collection is IList)
      {
        ((IList)_collection).Remove(this.Current);
      }
      else if (_collection is IDictionary)
      {
        ((IDictionary)_collection).Remove(this.Current);
      }
    }

    /// <summary>
    /// Returns true if the iteration has more elements. (In other words, returns true 
    /// if next would return an element rather than throwing an exception.) 
    /// </summary>
    public bool HasNext 
    {
      get
      {
        if ( (_index >=-1) && (_index <(_items.Count-1)))
        {
          return true;
        }
        else
        {
          return false;
        }
      }
    }

  }


}