Paging using Linq-To-Sql based on two parameters in asp.net mvc
As two parameters i say currentPage
and pagesize
.....I thus far used sql server stored procedures and implemented paging like this,
GO
ALTER PROCEDURE [dbo].[GetMa开发者_如何转开发terialsInView]
-- Add the parameters for the stored procedure here
@CurrentPage INT,
@PageSize INT
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
SELECT *,ROW_NUMBER() OVER (ORDER BY Id) AS Row FROM
(
SELECT
*,ROW_NUMBER() OVER (ORDER BY Id) AS Row
FROM InTimePagingView
) AS InTimePages
WHERE Row >= (@CurrentPage - 1) * @PageSize + 1 AND Row <= @CurrentPage*@PageSize
SELECT COUNT(*) as TotalCount FROM InTimePagingView
SELECT CEILING(COUNT(*) / CAST(@PageSize AS FLOAT)) NumberOfPages
FROM InTimePagingView
END
Now i am using Linq-to-sql and i use this,
public IQueryable<MaterialsObj> FindAllMaterials()
{
var materials = from m in db.Materials
join Mt in db.MeasurementTypes on m.MeasurementTypeId equals Mt.Id
where m.Is_Deleted == 0
select new MaterialsObj()
{
Id = Convert.ToInt64(m.Mat_id),
Mat_Name = m.Mat_Name,
Mes_Name = Mt.Name,
};
return materials;
}
Now i want to return the records,TotalCount
where i use Total count to generate pagenumbers..... Is this possible... Any suggestion...
EDIT:
Just found this...
NorthWindDataContext db = new NorthWindDataContext();
var query = from c in db.Customers
select c.CompanyName;
//Assuming Page Number = 2, Page Size = 10
int iPageNum = 2;
int iPageSize = 10;
var PagedData = query.Skip((iPageNum - 1) * iPageSize).Take(iPageSize);
ObjectDumper.Write(PagedData);
You can do it "by hand" with IQueryable.Skip(), .Take(), and .Count(), or you can use this handy pattern:-
public class PagedList<T> : List<T>
{
public PagedList(IEnumerable<T> source, int index, int pageSize)
{
this.TotalCount = source.Count();
this.PageSize = pageSize;
this.PageIndex = index;
this.AddRange(source.Skip(index * pageSize).Take(pageSize).ToList());
}
public int TotalCount { get; set; }
public int PageIndex { get; set; }
public int PageSize { get; set; }
public bool HasPreviousPage
{
get
{
return (PageIndex > 0);
}
}
public bool HasNextPage
{
get
{
return ((PageIndex + 1) * PageSize) < TotalCount;
}
}
}
Use it like this:-
public ActionResult Materials(int page)
{
var materials = MaterialsRepository.FindAllMaterials();
var results = new PagedList<MaterialsObj>(materials, page - 1, 10);
return new View(results)
}
There are a bunch of implementations around the internet with helpers and tests and all that jazz. I think it was ScottGu that came up with the original code, but don't quote me on that.
- http://pagedlist.codeplex.com/
- http://www.squaredroot.com/2009/06/15/return-of-the-pagedlist/
- http://blog.wekeroad.com/blog/aspnet-mvc-pagedlistt/
- http://mha.dk/post/LINQ-and-PagedList.aspx
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