如何从用户控件更新控件的ID

Question

I have a aspx page which have a div control id="mainblock"

I created a usercontrol which retrieves a value dynamically depending on the landing page.

I have to pass this value as an id tot he div id="mainblock" so that its id is changed to the value.

i am trying lot of things but not able to work at all.

first i tried to write a server side code in the user control to update like this

 protected void Page_Load(object sender, EventArgs e)
    {
     divid = dynamicid();

        var control = this.Page.FindControl("mainblock");
        if (control != null)
        {
            control.ID = divid.ToString();                
        }
       }

this does nothing it doesnot change the id of the DIV in the parent page.

i tried using javascript so that copy the innertext from the control of user control and update the current page control id like this

 <script type="text/javascript">
    document.getElementById('mainblock').id = document.getElementById('<%=   usercontrolidvalue.ClientID %>').innerText;
    </script>

which gives me this error.. Only Content controls are allowed directly in a content page that contains Content controls.

is there a way i can update the current id of a control from a usecontrol

any help please

Answer 1

You can not change the Value of the ID from code-behind. You can, however, set the client ID from the aspx code.

Do you have a finite set of id values? Then you could do like this in the aspx:

<div runat="server" clientidmode="Static" id="div1">one</div>
<div runat="server" clientidmode="Static" id="div2">two</div>
<div runat="server" clientidmode="Static" id="div3">three</div>
<div runat="server" clientidmode="Static" id="div4">four</div>

And then from your code-behind set the visibility as you need:

//Condition...
div1.Visible = false; //will not render
div2.Visible = false; //will not render  
div3.Visible = false; //will not render
div4.Visible = true; //the only one shown

This will leave only div four in your output HTML.