Solved

Checkboxlist - set checked status from database

Posted on 2006-11-07
6
1,430 Views
Last Modified: 2009-07-29
I have a checkboxlist bound to an object data source in a VB ASP.NET 2.0 environment.

My object datasource returns a three column sqlDataReader with the following columns: "TagName", "TagID", "Selected". The "Selected" column is boolean. I set the "DataTextField" = "TagName" and the "DataValueField" = "TagID". Unfortunately there is no "DataCheckedField" property to set the selected status of the check box to the value from the "Selected" column.

When I load the checkboxlist I want the items for which  the "Selected" field from the database equals "True" to be selected in the checkboxlist. What is the easiest way to do this? If the answer involves setting it with code which it probably does, please use VB.

Note: I have no problem writing back the user's selections to the database.
0
Comment
Question by:glebn
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
  • 2
6 Comments
 
LVL 12

Expert Comment

by:renjurdevan
ID: 17896337
In page load

for (int i = 0; i < CheckBoxList1.Items.Count; i++)
        {
            CheckBoxList1.Items[i].Selected = true;
        }

regards
Renju
0
 
LVL 12

Assisted Solution

by:renjurdevan
renjurdevan earned 100 total points
ID: 17896345
i mean loop thru reader and set "DataCheckedField"

CheckBoxList1.Items[i].Selected =   //convert to boolean and set salData("DataCheckedField")
0
 
LVL 4

Author Comment

by:glebn
ID: 17903718
Thanks for responding Renju, but I'm sorry your comments didn't answer my question. Your second comment was too vague and it didn't use VB. Telling me to loop through and set the box tells me nothing about how to do this most effectively. Again, thanks for responding.

I solved my own problem. My fundamental mistake was trying to use one datasource to build the list and set the values. Being an ASP.NET newbie I did this because I expected to be able to use the boolean "Selected" field to set the check box "checked" status which I now see that I can't. Instead, I used a datasource to populate the CheckboxList which included all possible rows ignoring the "Selected" field. I then created a different data source pulling only the rows for which selected was true. This second data source I used for the sqlReader in the code below to loop through the checkboxlist items during page load to check the appropriate items.

If sqlReader.HasRows Then
      Do While sqlReader.Read()
            For Each li As ListItem In Me.chkblCategories.Items
                  If li.Value = sqlReader("TagID") Then
                        li.Selected = True
                  End If
            Next
      Loop
Else
        ' If sqlReader doesn't have rows then no items should be selected.
      For Each li As ListItem In Me.chkblCategories.Items
            li.Selected = False
      Next
End If
sqlreader = Nothing

If anybody has suggestions for improving this or alternate approaches to the problem I would be glad to award the points.

0
Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 
LVL 12

Accepted Solution

by:
sandip132 earned 400 total points
ID: 17904845
Do you mean by like this? :

If sqlReader.HasRows Then
    Do While sqlReader.Read()
      i=0
     While i < MyList.Items.Count
      Dim chklst As CheckBoxList = CType(MyList.Items(i).FindControl("CheckBoxList1"), CheckBoxList)
      quantity = Int32.Parse(quantityTxt.Text)
      If chklst .value = sqlReader("TagID") Then
        chklst .Checked = True Then
      End If
      i=i+1:
    End While
   Loop
End IF

0
 
LVL 4

Author Comment

by:glebn
ID: 17920010
Both work fine. I prefer the For-Next loop because it is easier to read--don't know which method would be faster but the number of checkboxes are so small that it doesn't matter.

P.S. My Else clause was written a little to late at night ;) -- as written it doesn't clear checkboxes properly in some cases. I fixed it by removing the Else clause entirely and putting the clear all checkboxes code before the initial If-Then.

Thanks for the comment.

0
 
LVL 4

Author Comment

by:glebn
ID: 17933945
I actually decided to use my solution posted above, but appreciate both responses which were correct solutions. I gave sandip132 most of the points because s/he gave a detailed solution with VB code.
0

Featured Post

Announcing the Most Valuable Experts of 2016

MVEs are more concerned with the satisfaction of those they help than with the considerable points they can earn. They are the types of people you feel privileged to call colleagues. Join us in honoring this amazing group of Experts.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Lots of people ask this question on how to extend the “MembershipProvider” to make use of custom authentication like using existing database or make use of some other way of authentication. Many blogs show you how to extend the membership provider c…
One of the pain points with developing AJAX, JavaScript, JQuery, and other client-side behaviors is that JavaScript doesn’t allow for cross domain request for pulling content. For example, JavaScript code on www.johnchapman.name could not pull conte…
With Secure Portal Encryption, the recipient is sent a link to their email address directing them to the email laundry delivery page. From there, the recipient will be required to enter a user name and password to enter the page. Once the recipient …

735 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question