CODEWITHSUNDEEP
c#asp.netcode-behind
Luis Quijada
Luis Quijada

Reputation: 2405

Access parent DIV of user-control (ascx) from its code behind

From within the code-behind of an ASP .NET web user-control (ascx) I need to get access (at runtime) to its parent, a div element. The aim is simple as to modify the visibility of the mentioned parent div.

I can not touch so much of the web-page code so I'd need a solution requiring only modifications in the user-control's code behind.

So in the HTML "part" of the code of the web page I have this:

<div id="parentDIV" runat="server">
    <uc:MyUserControl ID="myUserControlInstance" runat="server" />
</div>

I'd like to do in the code behind of the user-control something like this:

this.Container.Visible = false;

Note that I'm not asking if it is a good practise or not to do this.

EDIT: The user-control code behind does not "know" about the ID of the parent DIV.

Upvotes: 2

Views: 9653

Answers (5)

user2156940
user2156940

Reputation: 91

Am I missing something, it sounds like you have a usercontrol and an aspx page (both have code behind's). The user control appears to have been added to the aspx page, wrapped in a div. YOu've made the div control runat server (though you can still do this via htmlcontrol). All you ned to do to manage the div is:

parentDIV.visible = false;

or whatever you need to do with the div.

Why does the UC code behind need to know about the APSX pages DIV, it doesn't.

Upvotes: 0

DancesWithBamboo
DancesWithBamboo

Reputation: 4156

I would hide it on the client. Decorate your user control container (div?) with a class like "awesomeUserControl". Then emit some javascript using the ScriptManager object to hide the parent like this:

ScriptManager.RegisterStartupScript(this, this.GetType(), "HideMyAwesomeUserControl", "$('.awesomeUserControl').parent().hide();", true);

Upvotes: 2

Jeremy
Jeremy

Reputation: 9030

The better way...

What you should do is to create a custom event in your user control, to which your container will subscribe - very much like subscribing to a button event, only this is your custom control. This event passes information to your container which can then discern from it what it needs, such as whether or not the div should/not be visible.

It might look something like:

protected void Page_Load(object sender, EventArgs e)
{
    this.myuserControl.Update += new MyUserControlUpdateEventHandler(myuserControl_Update);
}

void myuserControl_Update(object sender, MyuserControlEventArgs e)
{
    this.parentDiv.visible = !e.ShouldHideUI;
}

This method will decouple your parent with the user control, i.e. your user control doesn't have to have any knowledge at all of the parent's controls, nor should it.

If you are curious, here is a rough example of how your user control will define such an event:

public class MyuserControlEventArgs : EventArgs 
{
    public bool ShouldHideUI { get;set;}
    public MyuserControlEventArgs (bool shouldHideUI) 
    {
         this.ShouldHideUI = shouldHideUI;
    }
}
public delegate void MyUserControlUpdateEventHandler(object sender, MyuserControlEventArgs e);
public event MyUserControlUpdateEventHandler Update;
protected void OnUpdate(MyuserControlEventArgs e)
{
    if (Update!= null)
        Update(this, e);
}

Your user control will simply need to call OnUpdate whenever it feels its subscribers need to know about it.

The Quick and Dirty way...

If you need quick and dirty, then try this (inside your user control):

TheParentControl parentControl = (TheParentControl)this.Parent;
parentControl.ParentDiv.Visible = true;

The key is to cast to the appropriate type (apparently your user control would know what type of parent it has), then set the parent's property. You might expose your div as a property in the parent control. Note, that parent could be ANY control (page, FooControl, BarControl, whatever) whose control collection your user control resides. Once you get a handle to the parent, you can even FindControl() to find a control by name.

Upvotes: 1

Pankaj
Pankaj

Reputation: 10105

When all controls get rendered, the HTML Parent child controls can be determined like below.

I am using while loop, so in case you add some other intermediate control, it may not give crash or unexpected results.

public Control ParentControl
{
    get
    {
        Control ctl = this.Parent;
        while (true)
        {
            if (ctl == null) break;
            if (ctl.ID.Equals("parentDIV"))
            {
                break;
            }
            ctl = ctl.Parent;
        }
        return ctl;
    }
}

if(ParentControl != null)
    ParentControl.Visible = true|false;

Upvotes: 0

Mr. TA
Mr. TA

Reputation: 5359

You're almost there....

this.Parent.Visible = false;

Upvotes: 0

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