子页面中的母版页标签可见性

Question

I want to make a label invisible in child page which is defined in master page. Is there a way to do that?

Answer 1

((Label)Master.FindControl("mylbl")).Visible = false;

put this in page load of the child page , mylbl refers to the ID of the label

it might be Master.Page.FindControl .... now that I think of it, it's been a while , but that's how you do it

Answer 2

You should use javascript. Normally in this situation, you would reference your label using (assuming your label's ID is my_label_id)

document.GetElementById('<%= my_label_id.ClientId %>')

. . . or if you are using jquery . . .

$('#<%= my_label_id.ClientId %>')

However, AFAIK you cannot use clientid to reference a server-side control located on the master page from a content page. So I would either give the control a unique class name using the asp.net label attribute CssClass="myLabelClass" or retrieve the client Id by building the page, viewing the source, and finding the client ID. Steps for this can be found here: How to use javascript in content page, asp.net

Once you correctly reference the item, simply change the "display" style attribute to "none" as seen below. Using jQuery and assuming your CssClass name is myLabelClass :

$('.myLabelClass').css('display','none');

If you wanted this to occur on page load you could do the following:

$(function(){
    $('.myLabelClass').css('display','none');
});