Solved

Dropdown list as query criteria

Posted on 2009-04-14
7
281 Views
Last Modified: 2013-11-26
Hi, I have one dropdown list, populated with a database table that acts as a query criteria. Everything works fine. However, how can I add a blank value in the dropdown list, ontop of the other values, so it acts as a return all values ? Thanks
0
Comment
Question by:GPSAddict
  • 4
  • 3
7 Comments
 
LVL 14

Expert Comment

by:GiftsonDJohn
ID: 24141214
Hi,

To add a blank value in the top of a dropdown list

DropDownList1.Items.Insert(0, new ListItem(string.Empty, string.Empty))
0
 

Author Comment

by:GPSAddict
ID: 24141407
GiftsonDJohn: what event should I use ?
0
 
LVL 14

Accepted Solution

by:
GiftsonDJohn earned 500 total points
ID: 24141439
On the Page_Load event after you bind the dropdown list, you can use the function.

ex.

DropDownList1.DataSource=DataTable1;
DropDownList1.DataTextField="Column1";
DropDownList1.DataValueField="Column2";
DropDownList1.DataBind();

//Data Binding is Complete. Now we can add blank item into dropdownlist

DropDownList1.Items.Insert(0, new ListItem(string.Empty, string.Empty));
0
3 Use Cases for Connected Systems

Our Dev teams are like yours. They’re continually cranking out code for new features/bugs fixes, testing, deploying, testing some more, responding to production monitoring events and more. It’s complex. So, we thought you’d like to see what’s working for us.

 

Author Comment

by:GPSAddict
ID: 24144328
GiftsonDJohn: The reason I was asking is I didn't write a single line of code...everything going through the objects...So is there an event that happens just after the binding is complete ? Thanks
0
 

Author Comment

by:GPSAddict
ID: 24158918
Hello ?
0
 
LVL 14

Expert Comment

by:GiftsonDJohn
ID: 24161881
Hi,

Sorry. Got held in my work. All the Data Bound Control will fire DataBound event after every bindings. If you want to code for to return all values if blank value is selected then you have to write query so that it checks for the blank value and return the entire data.

if(DropDownList1.SelectedValue().Equals(string.Empty))
{
    //Query to extract all records
}
else
{
   //Query to extract record based on the dropdown value
}
0
 

Author Comment

by:GPSAddict
ID: 24167603
Doesn't seem to work, index 0 is already used since the dropdownlist is already populated with my database items ?! Anymore ideas ? Thanks
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

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

Introduction This article shows how to use the open source plupload control to upload multiple images. The images are resized on the client side before uploading and the upload is done in chunks. Background I had to provide a way for user…
More often than not, we developers are confronted with a need: a need to make some kind of magic happen via code. Whether it is for a client, for the boss, or for our own personal projects, the need must be satisfied. Most of the time, the Framework…
This is a video describing the growing solar energy use in Utah. This is a topic that greatly interests me and so I decided to produce a video about it.
This is a video that shows how the OnPage alerts system integrates into ConnectWise, how a trigger is set, how a page is sent via the trigger, and how the SENT, DELIVERED, READ & REPLIED receipts get entered into the internal tab of the ConnectWise …

919 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

Need Help in Real-Time?

Connect with top rated Experts

16 Experts available now in Live!

Get 1:1 Help Now