CheckBoxList - When does it actually databind?

30 Dec 2005 3:48 AM

beaudetious

I've got an ASP.NET 2.0 form with a checkboxlist control bound to a
SqlDataSource control. In the page's Page_Load event I want to loop through
the items in this CheckBoxList and programmatically select a few items.
However, when I do this in a foreach block I find that the ItemsCollection
contains 0 items. So, when is the best place to perform this task if not the
Page_Load event (checking for !IsPostBack of course).

Thanks,
beaudetious

30 Dec 2005 4:40 AM

Phillip Williams

The event DataBound marks the completion of the control databinding:

//At this stage the control is not databound yet. The list count is 0
 void Page_Load(Object sender, EventArgs e)
 {
 Response.Write(" Page_Load: CheckBoxList1.Items.Count= " +
CheckBoxList1.Items.Count);
 }
 //the databound event is raised when the control is databound
 void CheckBoxList1_DataBound(object sender, EventArgs e)
 {
 //this should print the total number of ListItems
 Response.Write(" CheckBoxList1_DataBound:
CheckBoxList1.Items.Count= " + CheckBoxList1.Items.Count);
 foreach (ListItem li in CheckBoxList1.Items)
 {
 //process each listitem
 }
 }
 //At this stage the control is populated.
 void Page_PreRenderComplete(object sender, EventArgs e)
 {
 Response.Write(" Page_PreRenderComplete:
CheckBoxList1.Items.Count= " + CheckBoxList1.Items.Count);
 }

--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com

Show quoteHide quote

"beaudetious" wrote:

> I've got an ASP.NET 2.0 form with a checkboxlist control bound to a
> SqlDataSource control. In the page's Page_Load event I want to loop through
> the items in this CheckBoxList and programmatically select a few items.
> However, when I do this in a foreach block I find that the ItemsCollection
> contains 0 items. So, when is the best place to perform this task if not the
> Page_Load event (checking for !IsPostBack of course).
>
> Thanks,
> beaudetious

30 Dec 2005 11:14 PM

beaudetious

I ended up just calling the CheckBoxList's DataBind() routine inside of
Page_Load and I get what I need. Thanks.

Show quoteHide quote

"Phillip Williams" wrote:

> The event DataBound marks the completion of the control databinding:
>
> //At this stage the control is not databound yet. The list count is 0
> void Page_Load(Object sender, EventArgs e)
> {
> Response.Write(" Page_Load: CheckBoxList1.Items.Count= " +
> CheckBoxList1.Items.Count);
> }
> //the databound event is raised when the control is databound
> void CheckBoxList1_DataBound(object sender, EventArgs e)
> {
> //this should print the total number of ListItems
> Response.Write(" CheckBoxList1_DataBound:
> CheckBoxList1.Items.Count= " + CheckBoxList1.Items.Count);
> foreach (ListItem li in CheckBoxList1.Items)
> {
> //process each listitem
> }
> }
> //At this stage the control is populated.
> void Page_PreRenderComplete(object sender, EventArgs e)
> {
> Response.Write(" Page_PreRenderComplete:
> CheckBoxList1.Items.Count= " + CheckBoxList1.Items.Count);
> }
> --
> HTH,
> Phillip Williams
> http://www.societopia.net
> http://www.webswapp.com
>
>
> "beaudetious" wrote:
>
> > I've got an ASP.NET 2.0 form with a checkboxlist control bound to a
> > SqlDataSource control. In the page's Page_Load event I want to loop through
> > the items in this CheckBoxList and programmatically select a few items.
> > However, when I do this in a foreach block I find that the ItemsCollection
> > contains 0 items. So, when is the best place to perform this task if not the
> > Page_Load event (checking for !IsPostBack of course).
> >
> > Thanks,
> > beaudetious