Web Standard build station checksum common errors

Web|web Standard | error

We use XHTML+CSS to redesign our site, how do we know that our own pages really conform to Web standards? The Web site and some volunteer websites provide online calibration programs to help us check whether the page meets the standards and provide help for correcting errors. These checksums are very useful and are the first thing I want to do when I debug the page.

　　1.XHTML Checksum

Verification URL: http://validator.w3.org/

Check mode: URL check, file upload check

The checksum is successful and displays "This Page is Valid XHTML 1.0 transitional!."

Checksum fails, more checksum options and error messages are displayed.

General selection of "show Source" and "Verbose Output" can help you find the error code and the reason for the error.

XHTML checksum common error reason tables

No DOCTYPE found! Falling back to HTML 4.01 transitional--undefined doctype.

No Character Encoding found! Falling back to utf-8.--does not have a defined language encoding.

End tag for "IMG" omitted, but Omittag no is specified--picture label is not added "/" off.

An attribute value specification must a attribute value literal unless Shorttag YES is specified--property values must be quoted.

Element "div" Undefined---div tag cannot be capitalized, to be converted to lowercase div.

Required attribute "alt" not specified---picture requires an Alt property.

Required attribute "Type" is not specified---JS or the label of the CSS call misses the Type property.

One of the most common bugs is the case of a label. Usually these errors are related, such as forgetting a different tag will be an error, so do not see a bunch of false fear, usually solve a mistake, the other mistakes are gone.

　　2.CSS2 Check

Verification URL: http://jigsaw.w3.org/css-validator/

Check mode: URL check, file upload check, directly into the code check

Verification success, will show "Congratulations congratulations, this document has been through the stylesheet checksum!" "。

Checksum fails, two types of errors are displayed: errors and warnings. Error indicates must be fixed, otherwise cannot pass checksum, warning indicates that the code is not recommended by the consortium, proposed modification.