Themes and Skins in ASP.NET 2.0

When you build a Web application, it usually has a similar look and feel across all its pages. Not too many applications are designed with each page dramatically different from the next. Generally, for your applications you use similar fonts, colors, and server control styles across all the pages.

You can apply these common styles individually to each and every server control or object on each page, or you can use a new capability provided by ASP.NET 2.0 to centrally specify these styles. All pages or parts of pages in the application can then access them.

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How to apply themes
Themes can be used by a variety of methods. The following examples show you how you can define a theme named "SmokeAndGlass" in your application by different methods:

<%@ Page Theme="SmokeAndGlass" Language="C#"%>
Themes can be set programmatically under the Page_PreInit event handler. It is necessary to define them in this event handler as all the looks are applied to the server controls defined in a particular theme before the page loads. Here is how you can set themes programmatically:


protected void Page_PreInit(object sender, EventArgs e)
{
string theme = "";
if (Page.Request.Form.Count > 0)
{
theme = Page.Request["Themes"].ToString();
if (theme == "Default")
{
theme = "";
}
}
this.Theme = theme;
}