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ContentAreaCssFile vs. CssFiles

Here you can examine some major differences regarding custom content area stylization via ContentAreaCssFile property and CssFiles collection.

The two approaches give you solutions to decorate and customize the content area of RadEditor. However, both of them differ in concepts and behave differently. The following sections will provide a clear view of the logic behind their differences and will help you to decide which approach to use.

This approach is available only when ContentAreaMode is iframe. Using a content area rendered as a DIV element does not offer native capabilities to add external CSS files. You can find out how to decorate the DIV content area here—Decorating Div Content Area.

Using ContentAreaCssFile property

  • Does not prevent styles from the main page from decorating the content area of RadEditor (i.e., any global styles that decorate your page will also decorate the editor's content area);
  • All styles from the ContentAreaCssFile will not decorate the content in Preview mode;
  • All styles form the ContentAreaCssFile file can be toggled via the Show/Hide Border tool;
  • Only a single external CSS file can be used for custom stylization;
  • Classes from the ContentAreaCssFile stylesheet will not be present in the Apply CSS Class dropdown;
  • Its concept is to provide user-friendly styling for creating the content, which is not part of the styling of the place where the content will be used.

Using CssFiles collection

  • Its concept is to let the end user see what their content will look like when used;
  • Does not affect the built-in ContentAreaCssFile—preserves the designed user-friendly experience with content editing;
  • Stops CSS style propagation and inheritence from the main page;
  • Allows CSS files to be changed/added/removed dynamically;
  • Can be configured with various techniques—via markup, XML file and from the code behind;
  • Multiple CSS files can be injected into the content area;
  • Custom styles cannot be toggled by the Show/Hide tool;
  • Custom styles affect both Design and Preview modes.

If you only want to stop the page style inheritance, you do not need to have a special blank stylesheet. An empty value for the CssFile will have the same effect and will avoid the unnecessary request:

- - -
    <telerik:RadEditor RenderMode="Lightweight" ID="RadEditor1" runat="server">
            <telerik:EditorCssFile Value="" />

See Also

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