nhibernate特殊查询-->Or查询

　　查询咨询表如下：

　　第一种查询：查询author1和author2的所有数据（注：作者不确定数量）

var array = new string[] { "author1", "author2" };

entitys = entitys.Where(x => array.Contains(x.Author));

　　第二种查询：查询描述中包含“新闻”和“公告”的所有数据（注：类似“新闻”等关键词不确定数量）

var array = new string[] { "新闻", "公告" };

entitys = entitys.Where(Toolkit.Utility.LambdaHelper.GenerateLambda<Data.DomainModels.Actionrecord>("Content", array, "Contains"));

　　GenerateLambda方法代码如下：

/// <summary>
/// 动态生成Lambda
/// </summary>
/// <typeparam name="T">对象类型</typeparam>
/// <param name="name">字段名称</param>
/// <param name="array">包含数据数组</param>
/// <param name="method">匹配方式</param>
/// <returns>lambda</returns>
public static Expression<Func<T, bool>> GenerateLambda<T>(string name, string[] array, string method)
{
    var param = Expression.Parameter(typeof(T), "x");

    var propertyName = Expression.Property(param, name);

    var body = Expression.Equal(Expression.Call(propertyName, method, null, Expression.Constant(array[0])), Expression.Constant(true));

    for (int n = 1; n < array.Length; n++)
    {
        body = Expression.OrElse(body, Expression.Call(propertyName, method, null, Expression.Constant(array[n])));
    }

    return Expression.Lambda<Func<T, bool>>(body, param);
}