| 以下为引用的内容： The <!DOCTYPE> declaration is the very first thing in your document, before the <html> tag. This tag tells the browser which HTML or XHTML specification the document uses. Note: The <!DOCTYPE> tag does not have an end tag! HTML HTML Strict DTD Use this when you want clean markup, free of presentational clutter. Use this together with Cascading Style Sheets (CSS): <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> The Transitional DTD includes presentation attributes and elements that W3C expects to move to a style sheet. Use this when you need to use HTML‘s presentational features because your readers don‘t have browsers that support Cascading Style Sheets (CSS): <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN" "http://www.w3.org/TR/html4/frameset.dtd"> XHTML Strict DTD Use this DTD when you want clean markup, free of presentational clutter. Use this together with Cascading Style Sheets (CSS): <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> Use this DTD when you need to use XHTML‘s presentational features because your readers don‘t have browsers that support Cascading Style Sheets (CSS): <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> Use this DTD when you want to use frames! <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd"> |
