解决方法@H_301_4@
2.5.2 Boolean attributes
A number of attributes are boolean attributes. The presence of a
boolean attribute on an element represents the true value,and the
absence of the attribute represents the false value.
If the attribute is present,its value must either be the empty string
or a value that is an ASCII case-insensitive match for the attribute’s
canonical name,with no leading or trailing whitespace.
The values “true” and “false” are not allowed on boolean attributes. To represent a false value,the attribute has to be omitted altogether.
2.5.2 Boolean attributes
A number of attributes are boolean attributes. The presence of a
boolean attribute on an element represents the true value,and the
absence of the attribute represents the false value.If the attribute is present,its value must either be the empty string
or a value that is an ASCII case-insensitive match for the attribute’s
canonical name,with no leading or trailing whitespace.The values “true” and “false” are not allowed on boolean attributes. To represent a false value,the attribute has to be omitted altogether.
