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Better way of making columns visible invisible

14 Answers 295 Views

GridView

This is a migrated thread and some comments may be shown as answers.

14 Answers, 1 is accepted

answered on 07 Jan 2008, 12:42 PM

I did some timing testing since I was having much the same problem,
and here is the information I got if it is any help:

First I set the old datasource to null and create an empty table. Then I
import rows from a datasource into my temporary table based on some rules,
then I set the grids datasource to the temporary table, set the columns
visible or not and fixes the header text for the columns.

There is (at the moment) no code for ordering the columns.

The table has 25 columns, and I import 17,467 rows into the temporary table.

---
Without Begin/end update:

Suspended layout (00:00:00)
Cleared datasource and created empty table (00:00:00)
Imported all rows (00:00:00.9843813)
Sat datasource (00:00:01.2968833)
Fixes column visibility and header text (00:00:06.2969217)
Ordered column (00:00:00)
Resumed layout (00:00:00)
Total time (00:00:08.5781863)

---

With begin/end update :

Suspended layout (00:00:00)
Cleared datasource and created empty table (00:00:00)
Imported all rows (00:00:00.9687562)
Sat datasource (00:00:01.3281335)
Fixes column visibility and header text (00:00:00.2031263)
Ordered column (00:00:00)
Resumed layout (00:00:00)
Total time (00:00:02.5000160)

---

As you can see, the time consuming bit was setting the columns visible
and setting the header text. The BeginUpdate/EndUpdate seems to have
removed this bottleneck. However, I thought the SuspendLayout/ResumeLayout
should have worked so it won't update when you are changing the layout, in
this case the visibility of the colunms. So that sort of confused me until I
read this thread and saw the begin/end thing.

answered on 30 Nov 2012, 09:40 AM

Do you have this problem with a current version of the controls?
I routinely have 50+ columns on grids (most of them initially invisible) with no noticeable lag.

Of course, you should make columns visible/invisible before
the grid initially displays and/or within BeginUpdate() / EndUpdate() or DeferRefresh()

Personally I prefer the

using(mygrid.DeferRefresh())

{

// do the stuff that potentially causes screen updates here

}

because it can be tricky to call EndUdate() on all code paths.