Dapper. Paging

I created a sample project to demo the Dapper custom paging, support sorting, criteria and filter:

https://github.com/jinweijie/Dapper.PagingSample

Basically, the method looks like this:

 Tuple<IEnumerable<Log>, int> Find(LogSearchCriteria criteria
        , int pageIndex
        , int pageSize
        , string[] asc
        , string[] desc);

The first return value is the item list. The second return value is the total count.

Hope it helps.

Thanks.

1) Dapper doesn't have a built-in pagination feature. But its not too hard to implement it directly in the query. Example:

SELECT  *
FROM    ( SELECT    ROW_NUMBER() OVER ( ORDER BY InsertDate) AS RowNum, *
          FROM      Posts
          WHERE     InsertDate >= '1900-01-01'
        ) AS result
WHERE   RowNum >= 1 // *your pagination parameters
    AND RowNum < 20  //*
ORDER BY RowNum

Requires SQL Server 2005+

2) Dapper returns an IEnumerable<T>.

You didn't specify a database or version. If you're lucky enough to be able to use the brand new SQL Server 2012 and have access to MSDN, you can use the shiny new OFFSET and FETCH keywords. The following query will skip 20 records and return the next 5.

SELECT * FROM [Posts]
ORDER BY [InsertDate]
OFFSET 20 ROWS
FETCH NEXT 5 ROWS ONLY

Check out http://msdn.microsoft.com/en-us/library/ms188385(v=sql.110).aspx#Offset for more info.

Also, it's easy enough to copy the way Massive does it and write your own extension method for IDbConnection. Here's Massive's code.

var query = string.Format("SELECT {0} FROM (SELECT ROW_NUMBER() OVER (ORDER BY {2}) AS Row, {0} FROM {3} {4}) AS Paged ", columns, pageSize, orderBy, TableName, where);

Here is a full working version using C# and Dapper.

/// <summary>
    /// Gets All People
    /// </summary>
    /// <returns>List of People</returns>
    public IEnumerable<Person> GetAllPeople(Pager pager)
    {
        var sql = (@" select * from [dbo].[Person]
                      order by [PeplNo]
                      OFFSET      @Offset ROWS 
                      FETCH NEXT  @Next   ROWS ONLY");

        using (IDbConnection cn = Connection)
        {
            cn.Open();

            var results = cn.Query<Person>(sql,pager);

            return results;
        }
    }


public class Pager
{
    public int Page { get; set; }
    public int PageSize { get; set; }

    public int Offset { get; set; }
    public int Next { get; set; }

    public Pager(int page, int pageSize = 10)
    {
        Page = page < 1 ? 1 : page;
        PageSize = pageSize < 1 ? 10 : pageSize;

        Next = pageSize;
        Offset = (Page - 1) * Next;
    }

}