用Moon.Orm来做分页数据显示

小弟来献丑了!最近弄一个自己的项目,底层使用Moon.Orm。有兴趣的可以看http://www.cnblogs.com/humble/p/3312018.html

至于好不好我说了不算,但是我自己用得还是蛮爽的。话不多说贴上关键代码

1.现实基于sql的分页方法,网上有很多高效分页预计,我只是选择一个比较合适的

CREATE PROCEDURE [dbo].[proc_DataPagingList]
(
@tableName NVARCHAR(200),      ----要显示的表或多个表的连接
@fieldNames NVARCHAR(200)='*', ----要显示的字段列表
@pageSize INT = 10,            ----每页显示的记录个数
@page INT = 10,                ----要显示那一页的记录
@pageCount INT = 1 output,     ----查询结果分页后的总页数
@counts INT = 1 output,        ----查询到的总记录数
@fieldSort NVARCHAR(200)= null,----排序字段列表或条件
@sort BIT = 1,                 ----排序方法,0为升序,1为降序--程序传参如:' SortA Asc,SortB Desc,SortC ')
@condition NVARCHAR(200)= null,----查询条件,不需WHERE
@keyID NVARCHAR(100),          ----主表的主键
@distinct BIT = 0              ----是否添加查询字段的 DISTINCT 默认0不添加/1添加
)
AS

SET NOCOUNT ON
Declare @SELECT NVARCHAR(1000)    ----存放动态生成的SQL语句
Declare @strCounts NVARCHAR(1000) ----存放取得查询结果总数的查询语句
Declare @strID  NVARCHAR(1000)    ----存放取得查询开头或结尾ID的查询语句

Declare @sortTypeA NVARCHAR(10)   ----数据排序规则A
Declare @SortTypeB NVARCHAR(10)   ----数据排序规则B

Declare @distSelect NVARCHAR(50)  ----对含有DISTINCT的查询进行SQL构造
Declare @distCounts NVARCHAR(50)  ----对含有DISTINCT的总数查询进行SQL构造

DECLARE @SortfieldA NVARCHAR(50)  ----对含有是否还有排序字段时的排序方式组合A
DECLARE @SortfieldB NVARCHAR(50)  ----对含有是否还有排序字段时的排序方式组合B


IF @distinct = 0
    BEGIN
        SET @distSelect = 'SELECT '
        SET @distCounts = ' COUNT(*)'
    END
ELSE
    BEGIN
        SET @distSelect = 'SELECT distinct '
        SET @distCounts = ' COUNT(DISTINCT '+@keyID+')'
    END

IF @sort=0
    BEGIN
        SET @SortTypeB=' ASC '
        SET @sortTypeA=' DESC '
    END
ELSE
    BEGIN
        SET @SortTypeB=' DESC '
        SET @sortTypeA=' ASC '
    END

IF @fieldSort IS NOT NULL AND @fieldSort<>'' --排序字段不为空时
    BEGIN
        SET @SortfieldB=' order by '+ @fieldSort +' '+ @SortTypeB
        SET @SortfieldA=' order by '+ @fieldSort +' '+ @SortTypeA 
    END
ELSE
    BEGIN
        SET @SortfieldB=''
        SET @SortfieldA=''
    END

--------生成查询语句--------
--此处@strCounts为取得查询结果数量的语句
IF @condition is null or @condition=''     --没有设置显示条件
    BEGIN
        SET @SELECT =  @fieldNames + ' FROM ' + @tableName
        SET @strCounts = @distSelect+' @counts='+@distCounts+' FROM '+@tableName
        SET @strID = ' FROM ' + @tableName
    END
ELSE
    BEGIN
        SET @SELECT = + @fieldNames + 'FROM ' + @tableName + ' WHERE  ' + @condition
        SET @strCounts = @distSelect+' @counts='+@distCounts+' FROM '+@tableName + ' WHERE ' + @condition
        SET @strID = ' FROM ' + @tableName + ' WHERE  ' + @condition
    END

----取得查询结果总数量-----
exec sp_executesql @strCounts,N'@counts INT out ',@counts out
DECLARE @tmpCounts INT

IF @counts = 0
    SET @tmpCounts = 1
ELSE
    SET @tmpCounts = @counts

    --取得分页总数
    SET @pageCount=(@tmpCounts+@pageSize-1)/@pageSize

    --/**当前页大于总页数 取最后一页**/
    IF @page>@pageCount
        SET @page=@pageCount

    --/*-----数据分页2分处理-------*/
    DECLARE @pageIndex INT --总数/页大小
    DECLARE @lastcount INT --总数%页大小 

    SET @pageIndex = @tmpCounts/@pageSize
    SET @lastcount = @tmpCounts%@pageSize
    IF @lastcount > 0
        SET @pageIndex = @pageIndex + 1
    ELSE
        SET @lastcount = @pageSize

    --显示分页
    IF @condition is null or @condition=''     --没有设置显示条件
    BEGIN
        IF @pageIndex<2 or @page<=@pageIndex / 2 + @pageIndex % 2   --前半部分数据处理
            BEGIN 
                SET @strCounts=@distSelect+' TOP '+ CAST(@pageSize as VARCHAR(4))+' '+ @fieldNames+' FROM '+@tableName + ' WHERE '+@keyID+' not in('+ @distSelect+' TOP '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @keyID +' FROM '+@tableName + @SortfieldB +')' + @SortfieldB 
            END
        ELSE
            BEGIN
            SET @page = @pageIndex-@page+1 --后半部分数据处理
                IF @page <= 1 --最后一页数据显示
                    SET @strCounts=@distSelect+' * FROM ('+@distSelect+' TOP '+ CAST(@lastcount as VARCHAR(4))+' '+ @fieldNames+' FROM '+@tableName + @SortfieldA+') AS TempTB '+@SortfieldB
                ELSE                
                    SET @strCounts=@distSelect+' * FROM ('+@distSelect+' TOP '+ CAST(@pageSize as VARCHAR(4))+' '+ @fieldNames+' FROM '+@tableName + ' WHERE '+@keyID+' not in('+ @distSelect+' TOP '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' '+ @keyID +' FROM '+@tableName + @SortfieldA+')' + @SortfieldA+') AS TempTB '+@SortfieldB
            END
    END

    ELSE --有查询条件
    BEGIN
        IF @pageIndex<2 or @page<=@pageIndex / 2 + @pageIndex % 2   --前半部分数据处理
        BEGIN 
                SET @strCounts=@distSelect+' TOP '+ CAST(@pageSize as VARCHAR(4))+' '+ @fieldNames +' FROM  '+@tableName + ' WHERE '+@keyID+' not in('+ @distSelect+' TOP '+ CAST(@pageSize*(@page-1) as Varchar(20)) +' '+ @keyID +' FROM '+@tableName + ' Where ' + @condition + @SortfieldB+')'+' AND ' + @condition + @SortfieldB                 
        END
        ELSE
        BEGIN 
            SET @page = @pageIndex-@page+1 --后半部分数据处理
            IF @page <= 1 --最后一页数据显示
                    SET @strCounts=@distSelect+' * FROM ('+@distSelect+' TOP '+ CAST(@lastcount as VARCHAR(4))+' '+ @fieldNames+' FROM '+@tableName + ' WHERE  '+ @condition +@SortfieldA+') AS TempTB '+@SortfieldB
            ELSE
                    SET @strCounts=@distSelect+' * FROM ('+@distSelect+' TOP '+ CAST(@pageSize as VARCHAR(4))+' '+ @fieldNames+' FROM '+@tableName + ' WHERE '+@keyID+' not in('+ @distSelect+' TOP '+ CAST(@pageSize*(@page-2)+@lastcount as Varchar(20)) +' ' + @keyID +' FROM '+@tableName +' WHERE  '+ @condition +@SortfieldA+')' +' AND '+ @condition +@SortfieldA+') AS TempTB ' + @SortfieldB 
        END    
    END

------返回查询结果-----
exec sp_executesql @strCounts
SET NOCOUNT OFF 

2.这是基于Moon.Orm的基类我拿来加了一个自己方法里面来用,

主要是看使用了ParameterDirection.Output来调取存储过程的返回值,就是总页数和每页显示的页数。
        public List<T2> GetPagingData<T2>(PageClass pc) where T2 : new()
        {
            DbParameter[] parameters = {
                       new SqlParameter("@tableName", SqlDbType.NVarChar,200) ,            
                        new SqlParameter("@fieldNames", SqlDbType.NVarChar,200) ,            
                        new SqlParameter("@pageSize", SqlDbType.Int,4) ,            
                        new SqlParameter("@page", SqlDbType.Int,4) ,            
                     new SqlParameter("@pageCount", SqlDbType.Int,4 ) ,            
                        new SqlParameter("@counts", SqlDbType.Int,4) ,            
                        new SqlParameter("@fieldSort", SqlDbType.NVarChar,200) ,            
                        new SqlParameter("@sort", SqlDbType.Bit,1) ,            
                        new SqlParameter("@condition", SqlDbType.NVarChar,200) ,            
                        new SqlParameter("@keyID", SqlDbType.NVarChar,100) ,            
                        new SqlParameter("@distinct", SqlDbType.Bit,1)                
              
            };



            parameters[0].Value = pc.sys_Table;
            parameters[1].Value = pc.sys_Fields;
            parameters[2].Value = pc.sys_PageSize;
            parameters[3].Value = pc.sys_PageIndex;
            parameters[4].Direction = ParameterDirection.Output;

            parameters[5].Direction = ParameterDirection.Output;
            parameters[6].Value = null;
            parameters[7].Value = 1;
            parameters[8].Value = pc.sys_Where;
            parameters[9].Value = pc.sys_Key;
            parameters[10].Value = 0;

           
            using (var db = Db.CreateDefaultDb())
            {
                //  db.DebugEnabled = true;
               
              List<T2>  list=  db.ExecuteProToOwnList<T2>("proc_DataPagingList", parameters);
              pc.RCount = Convert.ToInt32(parameters[5].Value);
              pc.PCount = Convert.ToInt32(parameters[4].Value);
                return list;
            }
        }

3.这是我弄的一个分页帮助类,方便赋值而已

 public class PageClass
    {
        /// <summary>
        /// 总页数输出
        /// </summary>
        public int PCount { get; set; }   // --
        /// <summary>
        /// 总记录数输出
        /// </summary>
        public int RCount { get; set; }   //--
        /// <summary>
        /// 查询表名
        /// </summary>
        public string sys_Table { get; set; }  // --
        /// <summary>
        /// 主键
        /// </summary>
        public string sys_Key { get; set; }     // --
        /// <summary>
        /// 查询字段
        /// </summary>
        public string sys_Fields { get; set; }  //  --
        /// <summary>
        /// 查询条件
        /// </summary>
        public string sys_Where { get; set; }   // --
        /// <summary>
        /// 排序字段
        /// </summary>
        public string sys_Order { get; set; }   //--
        /// <summary>
        /// 开始位置
        /// </summary>
        public int sys_Begin { get; set; }        //--
        /// <summary>
        /// 当前页数
        /// </summary>
        public int sys_PageIndex { get; set; }     //  --
        /// <summary>
        /// 页大小
        /// </summary>

        public int sys_PageSize { get; set; } // --
    }

最后个人使用感觉Moon.Orm速度很快,但是有些还有很有特点的语法,感兴趣可以去看看。暂时写了sql的分页,有些时间弄一些别的数据库的,欢迎大家赐教。不喜勿喷!谢谢

原文地址:https://www.cnblogs.com/xiaobaiczc/p/czc.html