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In the metrics rapid development platform, grid components are widely used. In general, if the data is less than 10,000, it can be queried directly and quickly. If the amount of data is large, it may be efficient to open it at one time. Therefore, there may be paging requirements for grid components to display data.

Although the paging display efficiency is improved after a large amount of data, it is still not convenient to view the data. If you do want to page, how can the paging function be implemented in the metric rapid development platform?

For mysql databases, paging is also easy to implement, and the function of limit paging is provided directly in sql. Metric rapid development platform is generally sqlserver or oracle, we can also use SQL statements to achieve paging effect.

The main implementation idea is to use SQL statements to query different data, and then build data similar to the previous page and the next page on the interface, the following are the implementation steps:

1. Set up the business table

When creating a business table, you need to consider the paging feature. The following code example is common to oracle and sqlserver:

Select * from

(

Select

ROW_NUMBER () over (order by id) as rownum

COUNT (*) over () rowscount

ID,TITLE,HEIGHT, WIDTH, CREATE_TIME, CREATE_USER from form_list

) t

Where rownum > = ([: PAGE]-1) * [: ROW] + 1 and rownum

< [：PAGE] * [:ROW]+1 说明： rownum表示每一行数据的序号，rowscount表示该查询的所有记录。 两个整数型的业务表变量 PAGE,ROW 分别表示页数，每页显示条数。 2、建立窗体 分别拖入一个网格部件，一个下拉选择（页选择），两个按钮（上页，下页）。 网格部件选择好上面建立的业务表。 2.1）窗体加载事件代码: '定义每页显示条数 dim PAGE_OF_ROW = 19 '定义页数，默认查询第一页 dim PAGE_NUM = 1 Call("刷新") '------------------------配置页选项功能开始---------------------------- '页选项刷新标志(0不刷新,1刷新) dim RefreshGlag=0 '总条数 dim allCount=网格部件1.GetFocusedRowValue("ROWSCOUNT") dim ALL_PAGE=0 '因为cint四舍五入了，为了保证有效行数，加0.4999,这样，小数点后有值的，就表示要多一页。 ALL_PAGE=cint(allCount/PAGE_OF_ROW+0.4999999) dim stringset="" for iLoop=1 to ALL_PAGE stringset=stringset+cstr(iLoop)+"," next if len(stringset)>

0 then

Stringset=left (stringset,len (stringset)-1)

Page option .SetItems (stringset,false)

Page option .value = PAGE_NUM

Else

Stringset= "1"

Page option .SetItems (stringset,false)

Page option .value = PAGE_NUM

End if

RefreshGlag=1

The text label 1.Text = "Total" & allCount & "data, per page" & PAGE_OF_ROW& "."

'- the end of the configuration page options function-

2.2) the page options are the same as the previous page and the next page code:

'The value of the page option changes the event event code:

If RefreshGlag=1 then

PAGE_NUM = page option .value

Call ("Refresh")

End if

'Click event event code on the previous page:

If cint (PAGE_NUM) > 1 then

PAGE_NUM = cint (PAGE_NUM)-1

Page option .value = PAGE_NUM

End if

'Click event event code for the next page:

If cint (PAGE_NUM) < ALL_PAGE then

PAGE_NUM = cint (PAGE_NUM) + 1

Page option .value = PAGE_NUM

End if

2.3) refresh the feature code:

'refresh the data

Grid component 1.SetVaribleValue ("PAGE", PAGE_NUM)

Grid component 1.SetVaribleValue ("ROW", PAGE_OF_ROW)

Grid part 1.RefreshData ()

3. Effect:

There are many ways to page. For others, please ask google to query sql pagination.

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Written by: measurement Technology http://www.delit.cn

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