Link to home
Start Free TrialLog in
Avatar of KaranGupta
KaranGupta

asked on

Problem in getting the control on runtime

Hi

I have created a web custom control.The class is inherited from TextBox class.
I have made a property called MTBID as ID of the control.

I can put that control on aspx page and everything is working fine, but when I try to access the control in code behind file.

It is not working well.
Avatar of Muhammad Ousama Ghazali
Muhammad Ousama Ghazali
Flag of Saudi Arabia image

Are you sure you made your property with Public rather than Private or Protected?
Avatar of KaranGupta
KaranGupta

ASKER

yes

public string MTBID
        {
            get;
            set;
        }      


Can you please paste the code how are you creating your custom control within ASPX Source.
Have you referenced it properly at the top of the page?
Here we go
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="WebApplication1._Default" %>
<%@ Register TagPrefix="FTB" Namespace="MultiPurposeTextBox" Assembly="MultiPurposeTextBox" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <FTB:MultiPurposeTextControl ID="karan"  MTBErrorMessageControlType="VALIDATIONSUMMARY"  MTBText="karan"
                 runat="server"></FTB:MultiPurposeTextControl>
    
    </div>
    </form>
</body>
</html>

Open in new window

You may be annoyed by these questions but...
Have you referenced the correct version of the assembly containing the control in this project?
And make sure that the DLL of the custom object is either registered within GAC or placed within bin folder of the current project.
After referencing, try closing the page from design and code behind mode. Re-open ASPX file in Design mode. Try double click anywhere on the form to move to code behind and see if you can now refernce your control or not. If you are still unable to do that, try creating a reference by yourself in the main .vb file of .designer.vb file and see if it gets to work.
 
Are you setting MTBID at runtime and it gets cleared on postback?
if so you'll need to keep the value in viewstate for example. See below how ASP.NET TextBox Text property is implemented.

you could also use the control like this without needing the viewstate implementation:
  <FTB:MultiPurposeTextControl ID="karan" MTBID="somevalue"  MTBErrorMessageControlType="VALIDATIONSUMMARY"  MTBText="karan"
                 runat="server"></FTB:MultiPurposeTextControl>



public virtual string Text
{
    get
    {
        string str = (string) this.ViewState["Text"];
        if (str != null)
        {
            return str;
        }
        return string.Empty;
    }
    set
    {
        this.ViewState["Text"] = value;
    }
}

Open in new window

Hi tetorvik

I think we need to specify some attribute over the property

so that we can use it as ID
Hi moghazali

Please don't hesitate in asking the question. I'll never be annoyed

Yes I have added the reference of the dll by "Add Reference"
Hi

I more thing I want to share is

there is another attribute called ID
 <FTB:MultiPurposeTextControl MTBID="karan122"  MTBErrorMessageControlType="LABEL"  MTBText="123"
                 runat="server"></FTB:MultiPurposeTextControl>

when I define ID then I can get the value in code behind but not in case of MTBID
ASKER CERTIFIED SOLUTION
Avatar of Muhammad Ousama Ghazali
Muhammad Ousama Ghazali
Flag of Saudi Arabia image

Link to home
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
I did not dig into details but this page may also give idea on the similar but necessarily the same issue:

http://msdn.microsoft.com/en-us/library/hw8sf6fb.aspx 
I think ID is really required. At least I haven't seen/found any attribute that would make a custom property to replace original ID property.
It also seems that if you declare a custom control without ID like:<FTB:MultiPurposeTextControl MTBID="karan122"  MTBErrorMessageControlType="LABEL"  MTBText="123" runat="server"></FTB:MultiPurposeTextControl>
the runtime generates a "random" ID for it. In that case it is really difficult to use the control in code-behind without knowing the ID. To use the control in code behind you would need to create a helper method to browser through the page controls and returns the correct control based on control type and MTBID attribute.

I think this can be done, but I don't think you should.