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PHP Build a Basic PHP Website (2018) Building a Media Library in PHP Adding Active States to the Navigation

Nikolay Komolov
Nikolay Komolov
23,033 Points

Why, when omitting "$section=null", are all links underlined?

Hello everyone :)

Could you explain to me, please, why are all the links underlined when no "$section=null" is set in "index.html"?


1 Answer

Chung-Jun Wang
Chung-Jun Wang
3,718 Points

If you do not add $section=null in index.html, then when it include header.php, variable $section is not defined.

So the condition in header.php <?php if($section == “books”){echo “on”;} ?> will fail because PHP can not compare the value, more precisely if($section == “anything”) always become true, then what PHP do is simply echo "on" no matter what value $section is.

So in the header every link will has class "on" which means they are all underlined.