C# 分页查询

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace Chillifish.Utils
{
//首页 上一页 ... 89 90 91 92 93 94  ...下一页 末页 跳转到[ ]页
public class PagedList<T> : List<T>
{
public int? PageIndex { get; private set; }//当前页码减一的值
public int PageSize { get; private set; } //每页显示行数
public int Start { get; private set; }//当前页面显示的第一个页号
public int End { get; private set; }//当前页面显示的最后一个页号
public int TotalPages { get; private set; }//总页数

/// <summary>
///
/// </summary>
/// <param name="source">列表元数据</param>
/// <param name="pageIndex">页码</param>
/// <param name="pageSize">每页显示数量</param>
public PagedList(IQueryable<T> source,int? pageIndex,int pageSize) {
PageIndex = (pageIndex ?? 0);//如果pageIndex存在，把pageIndex值进行赋值，否则赋值0
PageSize = pageSize;
//计算总页数 总记录数 / 每页行数 有余+1
TotalPages = (int)Math.Ceiling(source.Count() / (double)PageSize);

int size;//判定每个页面显示多少页号
if (TotalPages > 6)
{
size = 6;
//定义每个页面的页号从几开始
if (pageIndex > 2 && pageIndex < TotalPages - (size - 2)) {
Start = (pageIndex ?? 0) - 1;
}
else if (pageIndex >= TotalPages - (size - 2))
{
Start = TotalPages - size + 1;
}
else {
Start = 1;
}

}
else {
size = TotalPages;
Start = 1;
}

End = Start + size - 1;

//将数据分页后存入
//Skip : 从source的那一位下标开始
//Take:下标移动多少位
this.AddRange(source.Skip(PageSize * (PageIndex??0)).Take(PageSize));

}

}
}

public ActionResult Index(int? pageIndex,Person model)
{
var models = from m in db.Person select m;
if (!String.IsNullOrEmpty(model.PersonName)) {
//Contains相当于like查询，包含
models = models.Where(m => m.PersonName.Contains(model.PersonName));
}
ViewBag.PersonName = model.PersonName;

models = models.OrderBy(m=> m.PersonID);
PagedList<Person> pagedList = new PagedList<Person>(models, pageIndex, 5);
return View(pagedList);
}