在SQL中进行分页,网上已经有很多例子了,在这里我使用Linq to SQL让C#来生成分页代码,首先创建分页的扩展方法:
public static class Extensions
{
/// <summary>
/// 分页
/// </summary>
/// <param name="list"> 数据源 </param>
/// <param name="order"> 排序表达式 </param>
/// <param name="page"> 第几页 </param>
/// <param name="size"> 每页记录数 </param>
/// <param name="count"> 记录总数 </param>
/// <returns></returns>
public static IQueryable<T> Pagination<T,TKey>(this IQueryable<T> list, Expression<Func<T, TKey>> order, int page, int size, out int count)
{
count = list.Count();
return list.Distinct().OrderBy(order).Skip((page - 1) * size).Take(size);
}
}
然后在程序中调用起来也很方便(只需要在linq查询中直接调用扩展方法即可):
int count;
var q = (from a in context.WT_Tickets
join b in context.WT_OrderForm on a.OrderId equals b.Id
select new
{
BusNo = a.BusNumber,
OrderId = b.Id,
OrderDate = b.OrderDateTime,
}).Where(t=>t.OrderId.Length > 5).Distinct().Pagination(1, 10, out count);
var data = q.ToList();
另外一种分页方式,按偏移量和页面记录数来获取数据:
public static class Extensions
{
/// <summary>
/// 分页
/// </summary>
/// <param name="list">数据源</param>
/// <param name="offset">偏移量</param>
/// <param name="limit">查询记录数</param>
/// <param name="count">记录总数</param>
/// <returns></returns>
public static IQueryable<T> Pagination<T>(this IQueryable<T> list,int offset,int limit,out int count)
{
count = list.Count();
return list.OrderBy(t => t).Skip(offset).Take(limit);
}
}