If you want the CSS style sheet to take effect, the DOCTYPE statement is necessary. In the previous TABLE layout web page, the DOCTYPE can be omitted and it can be displayed normally. But if it is in a DIV CSS layout, this small piece of code in DOCTYPE is crucial and will affect whether the CSS style takes effect. Without the DOCTYPE html declaration, some CSS styles are still valid, but some CSS styles are invalid. So DOCTYPE is essential.
DOCTYPE abbreviation
In the previous HTML4 version (now HTML), when our DW software creates a new HTML, DOCTYPE will be automatically generated, and there is no need to enter it manually. It is very convenient and fast. Maybe you have never carefully observed what the DOCTYPE code means and what words it consists of.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml">
The default DW software comes with it when creating new HTML.
Although we do not need to manually enter the !DOCTYPE html code ourselves, abbreviations are popular in HTML5, and the above particularly long and complex code is abbreviated as:
<!DOCTYPE html> <html>
is compatible with all browsers, so there is no need to worry about compatibility issues or htmlgarbled code issues due to abbreviations.
It is best to abbreviate in DW software, so that it is not easy to change the encoding mode of the HTML web page. If Notepad modifies the abbreviated HTML file or program file, it will easily cause the web page to be garbled.
Simplifying code is a code fashion. If it can be abbreviated and has good compatibility, why wouldn't we do it! Therefore, DIVCSS5 recommends the abbreviation.
Come on:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml">
The abbreviation for slimming is:
<!DOCTYPE html> <html>
So demand determines the market. Our future codes will become more and more concise. For more exciting content, please pay attention to php Chinese NetOther related articles!
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