LINQ到XML查询

呼叫 ToList() 在查询结果上。然后将结果缓存在静态变量中,以线程安全方式访问:

private static List<Whatever> dropDownListValues;
private static object listLock = new object();

public static IList<Whatever> DropDownListValues
{
    get
    {
        lock(listLock)
        {
            if (dropDownListValues == null ||
                DetectValuesChanged()) // However you implement this!
            {
                dropDownListValues = // insert your query here
                                        .ToList();
            }
            return dropDownListValues;
        }
    }
}

使用标准缓存技术。请看 this post .