Linq to Object在测试中的应用

< ?xml version="1.0" encoding="utf-8" ?>
<onlinefriends>
    <friends>
        <onlinefrienddata>
            <friendid>1300010000</friendid>
            <province>北京市</province>
            <city>北京市</city>
            <age>18</age>
            <gender>2</gender>
            <hasphoto>true</hasphoto>
        </onlinefrienddata>
        <onlinefrienddata>
            <friendid>1300010002</friendid>
            <province>北京市</province>
            <city>北京市</city>
            <age>27</age>
            <gender>2</gender>
            <hasphoto>false</hasphoto>
        </onlinefrienddata>
        <onlinefrienddata>
            <friendid>1300010004</friendid>
            <province>广东省</province>
            <city>广州市</city>
            <age>45</age>
            <gender>1</gender>
            <hasphoto>true</hasphoto>
        </onlinefrienddata>
    </friends>
</onlinefriends>

[XmlRoot("OnlineFriends")]
public class OnlineFriends
{
	private bool IsEmpty = true;
 
	private static OnlineFriends fs = new OnlineFriends();
 
	private OnlineFriends()
	{ }
 
	public static OnlineFriends Instance
	{
		get
		{
			if (fs.IsEmpty)
			{
				fs.Deserialize();
			}
			return fs;
		}
	}
 
	private void Deserialize()
	{
		var serialzer = new XmlSerializer(typeof(OnlineFriends));
		using (XmlReader xmlreader = XmlReader.Create("OnlineFriends.xml"))
		{
			fs = serialzer.Deserialize(xmlreader) as OnlineFriends;
			fs.IsEmpty = false;
		}
	}
 
	public class OnlineFriendData
	{
		[XmlElement("FriendId")]
		public int FriendId { get; set; }
 
		[XmlElement("Province")]
		public string Province { get; set; }
 
		[XmlElement("City")]
		public string City { get; set; }
 
		[XmlElement("Age")]
		public int Age { get; set; }
 
		[XmlElement("Gender")]
		public byte Gender { get; set; }
 
		[XmlElement("HasPhoto")]
		public bool HasPhoto { get; set; }
	}
 
	[XmlArray("Friends")]
	[XmlArrayItem("OnlineFriendData")]
	public OnlineFriendData[] Friends { get; set; }
}

[TestMethod]
public void GetOnlineFriendsIdList_Query_Age_LowerUpperDiffOne()
{
	//重新初始化测试数据
	TestHelp.InitForSearch();
	int age = 27;
	OnlineFriendQuery query = new OnlineFriendQuery();
	query.AgeLowerBound = age;
	query.AgeUpperBound = age;
             //根据条件查询在线会员，在这里就是要查询27岁的会员
	List<int> ids = FriendListGateway.FriendListProvider.GetOnlineFriendsIdList(query, MyAllPc);
 
	//Two collects are equivalent
	CollectionAssert.AreEquivalent(OnlineFriends.Instance.Friends.Where(x => x.Age == age).Select(y => y.FriendId).ToList</int><int>(), ids);
}
</int>