How Can I Write Button Click Event For Master Page Buttons In Content Pages

In your master page's code behind replace the protected keyword on the event handler to public.

public void LinkButton1_Click(object sender, EventArgs e)
{
    //Do Stuff Here
}

IN your content page use the Master Type Directive

<![CDATA[<%@ MasterType VirtualPath="~/masters/SourcePage.master"" %>]]> 

In the code behind for the content page call the Master event handler as follows

protected void ImageButton1_Click(object sender, ImageClickEventArgs e)
{
    this.Master.LinkButton1_Click(sender, e);
}

See some good links for this point. And go through this you will bit clear more
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