473,796 Members | 2,648 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

problem with accessing control created dynamically

29 New Member
Dear All,

I am using asp.net2.0, C#, sql2005 using Visual studio 2005

Let Me explain the scenario I have checkboxlist containg 15 field. Based on no of checked field . I created dropdownlistbox and label dynamically through loop and assign id as dropdownlist + no of iteration. Now my question is how I access these control as when I am accessing one of the control I am getting nullobjectrefer ence error stating “Object reference not set to an instance of an object.”
I created control as

Foreach(listite m)
{

//…….
Label label = new Label();
DropDownList dropdownlist = new DropDownList();
//assinging id
label.ID = "label" + i.ToString() ;
dropdownlist.ID = "dropdownli st" + i.ToString() ;

}
And I am accessing it through

cmd.Parameters. Add("@para1", SqlDbType.VarCh ar).Value = Page.FindContro l("label1").ToS tring() ;
cmd.Parameters. Add("@value1", SqlDbType.VarCh ar).Value = Page.FindContro l("dropdownlist 1").ToString ();

and my second question is how do i access selected value in dropdownlist1(d ynamically created control) Please guide me

Thanks
Jul 26 '07 #1
4 1492
krris
10 New Member
Dear All,

I am using asp.net2.0, C#, sql2005 using Visual studio 2005

Let Me explain the scenario I have checkboxlist containg 15 field. Based on no of checked field . I created dropdownlistbox and label dynamically through loop and assign id as dropdownlist + no of iteration. Now my question is how I access these control as when I am accessing one of the control I am getting nullobjectrefer ence error stating “Object reference not set to an instance of an object.”
I created control as

Foreach(listite m)
{

//…….
Label label = new Label();
DropDownList dropdownlist = new DropDownList();
//assinging id
label.ID = "label" + i.ToString() ;
dropdownlist.ID = "dropdownli st" + i.ToString() ;

}
And I am accessing it through

cmd.Parameters. Add("@para1", SqlDbType.VarCh ar).Value = Page.FindContro l("label1").ToS tring() ;
cmd.Parameters. Add("@value1", SqlDbType.VarCh ar).Value = Page.FindContro l("dropdownlist 1").ToString ();

and my second question is how do i access selected value in dropdownlist1(d ynamically created control) Please guide me

Thanks

Hi
u r declare the label and Drop down in loop so when loop is over object scop is also over. if u declare label and dropdown out of loop with array then it will help u.
Jul 26 '07 #2
hellboss
50 New Member
Hello sir ! can u provide me with the code for creating a text box control array when a button is clicked ?
Aug 10 '07 #3
TRScheel
638 Recognized Expert Contributor
Hello sir ! can u provide me with the code for creating a text box control array when a button is clicked ?
What solutions have you tried? Have you considered a hidden frame that is visible once the button is clicked, then disposed of when no longer needed?
Aug 10 '07 #4
TRScheel
638 Recognized Expert Contributor
my second question is how do i access selected value in dropdownlist1(d ynamically created control) [/b] Please guide me

Thanks

You need to cast the found control to the proper type.

Expand|Select|Wrap|Line Numbers
  1. ((DropDownList)Page.FindControl("MyDropDownList"))
Aug 10 '07 #5

Sign in to post your reply or Sign up for a free account.

Similar topics

6
3334
by: Thomas | last post by:
Hi, I'm having a problem with the dynamically created inputfields in Internet Explorer. The situation is the following: - I have a dynamically created table with a textbox in each Cell. - It is possible to Add and Delete rows - Some cells have special attributes (readonly and events) Here's a snippet of the code:
3
2329
by: fumihiko | last post by:
Hi, I created an activex control (C++), and it uses another COM dll (C++). This COM dll links with a static library that dose some calculation. (both are debug multithreaded dll) I created a C# client having activex control embedded at the very beginning (added in the design window); then, I created another same activex control at the runtime. After the 2nd activex control is created, I start to get errors on the function calls to the...
3
2271
by: Eric | last post by:
I have built a composite user web control that I want to create dynamically. The form will contain a variable number of these controls and as well some of the contents of the user web control itself are dynamically created controls. I create as follows: wcGroupControl oGroupControl = new wcGroupControl(); I then tried calling methods of the control passing dynamic controls as parameters that need to be added to the web controls on the...
2
2931
by: R Duke | last post by:
I have tried everything I can think of to change the visible property of a design time created control from a dynamically created control's command event handler. Here is the scenario. I have a WebForm with some textboxes, dropdownlists, a panel, imagebutton and so on. When I click on the image button (which was created at design time) I dynamically build a table. In each of row of that new table I put several cells and one cell...
1
3024
by: Kamal Jeet Singh | last post by:
Hi Friends !! I am have facing problem in controlling the dynamically created controls on web page. The problem Scenario is Scenario:- My requirement is to load the web user controls on the web page dynamically. To do this, First I including a web page (MainPage.aspx) and I made form tag to Runat=Server. I included one table tag and also made this table Runat=Server side. Second I created three Web User Controls e.g....
1
2580
by: Kamal Jeet Singh | last post by:
Hi Friends !! I am facing problem in controlling the dynamically created controls on web page. The problem Scenario is Scenario:- My requirement is to load the web user controls on the web page dynamically. To do this, First I including a web page (MainPage.aspx) and I made form tag to Runat=Server. I included one table tag and also made this table Runat=Server side. Second I created three Web User Controls e.g. wucCustomerInfo.ascx,
2
1832
by: Richard Lionheart | last post by:
Hi All, I generated a WebForm and created a Virtual Directory for it IIS. But I got an error message (shown below) saying something like my app lacked appropriate privileges. David Wang replied to an earlier question about this issue, and he informed me that I needed to include my UserID in the "VS Developers" group in order to WebForm apps running under my account capable of accessing \\server\wwwroot$.
5
3068
by: Daniel Corbett | last post by:
I am trying to save a file dynamically created in a webpage. I get the following headers, but cannot figure out how to save the attachment. I am basically trying to replicate what internet explorer would do in this case. The headers I am getting are: Headers {Content-Disposition: attachment; filename="dynamic_file.mdb" Connection: close Cache-Control: private Content-Type: application/octet-stream
6
2864
by: hlubocky | last post by:
I thought I had a good grasp of the problem related to dynamically creating controls, but it appears that as my application grew in complexity, the problem has resurfaced. As I understand it, in order for a dynamically created control to persist its state, it needs to be created and loaded into the page control hierarchy before the viewstate is loaded. The proposed solution, and that which I have been using, has been to create all of...
0
9685
marktang
by: marktang | last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, we’ll explore What is ONU, What Is Router, ONU & Router’s main usage, and What is the difference between ONU and Router. Let’s take a closer look ! Part I. Meaning of...
0
9535
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it. First, let's disable language synchronization. With a Microsoft account, language settings sync across devices. To prevent any complications,...
0
10242
jinu1996
by: jinu1996 | last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven tapestry of website design and digital marketing. It's not merely about having a website; it's about crafting an immersive digital experience that captivates audiences and drives business growth. The Art of Business Website Design Your website is...
1
10200
by: Hystou | last post by:
Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
0
10021
tracyyun
by: tracyyun | last post by:
Dear forum friends, With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each protocol has its own unique characteristics and advantages, but as a user who is planning to build a smart home system, I am a bit confused by the choice of these technologies. I'm particularly interested in Zigbee because I've heard it does some...
0
9061
agi2029
by: agi2029 | last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing, and deployment—without human intervention. Imagine an AI that can take a project description, break it down, write the code, debug it, and then launch it, all on its own.... Now, this would greatly impact the work of software developers. The idea...
0
6800
by: conductexam | last post by:
I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and then checking html paragraph one by one. At the time of converting from word file to html my equations which are in the word document file was convert into image. Globals.ThisAddIn.Application.ActiveDocument.Select();...
0
5453
by: TSSRALBI | last post by:
Hello I'm a network technician in training and I need your help. I am currently learning how to create and manage the different types of VPNs and I have a question about LAN-to-LAN VPNs. The last exercise I practiced was to create a LAN-to-LAN VPN between two Pfsense firewalls, by using IPSEC protocols. I succeeded, with both firewalls in the same network. But I'm wondering if it's possible to do the same thing, with 2 Pfsense firewalls...
3
2931
bsmnconsultancy
by: bsmnconsultancy | last post by:
In today's digital era, a well-designed website is crucial for businesses looking to succeed. Whether you're a small business owner or a large corporation in Toronto, having a strong online presence can significantly impact your brand's success. BSMN Consultancy, a leader in Website Development in Toronto offers valuable insights into creating effective websites that not only look great but also perform exceptionally well. In this comprehensive...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.