Gets a value that indicates whether standards-compliant mode is switched on for the object.
Syntax
[ sMode = ] document.compatMode
Possible Values
| sMode | String that
receives one of the following values.BackCompat | Standards-compliant mode is not switched on. | CSS1Compat | Standards-compliant mode is switched on. |
|
The property is read-only.
The property has no default value.
Remarks
With Microsoft Internet Explorer 6 and later, you switch on standards-compliant mode by including the !DOCTYPE declaration at the top of your document, specifying a valid Label in the declaration, and in some cases, specifying the Definition or URL. The Label element specifies the unique name of the Document Type Definition (DTD), and can be appended with the version number of the DTD. The Definition element specifies the definition of the DTD that is specified in the Label. The URL element specifies the location of the DTD.
When standards-compliant mode is switched on (also called "strict mode"), Windows Internet Explorer displays the document according to the World Wide Web Consortium (W3C) Cascading Style Sheets (CSS) 
standard. When standards-compliant mode is not switched on (also called "quirks mode"), the document is displayed as it was displayed in previous versions of Internet Explorer.
Note This documentation is preliminary and is subject to change.
The compatMode property is deprecated in Internet Explorer 8 in favor of the documentMode property.
Examples
The !DOCTYPE declarations in the following examples specify conformance to the Transitional HTML 4.0 DTD. The declaration in the second example specifies the URL of the DTD. The declaration in the first example does not. The second declaration switches on standards-compliant mode with Internet Explorer 6 and later. The first declaration does not.
The compatMode property returns BackCompat with documents containing the declaration in the following example. This declaration does not switch on standards-compliant mode because it does not specify the URL of the Transitional HTML 4.0 DTD.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
This feature requires Microsoft® Internet Explorer 6 or later. Click the following icon to install the latest version. Then reload this page to view the sample.
The compatMode property returns CSS1Compat with documents containing the declaration in the following example. This declaration switches on standards-compliant mode because it specifies the URL of the Transitional HTML 4.0 DTD.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
This feature requires Microsoft® Internet Explorer 6 or later. Click the following icon to install the latest version. Then reload this page to view the sample.
Standards Information
There is no public standard that applies to this property.
Applies To
See Also
documentMode, CSS Enhancements in Internet Explorer 6