Use of the PHP delimiter EOF

PHP is a web programming language, in the programming process will inevitably encounter with Echo to output a large segment of HTML and JavaScript script, if the traditional output method-by string output,

There must be a large number of escapes to escape special characters such as quotes in a string to avoid syntax errors. If it is one or two, it can be tolerated,

But if a complete HTML text or a 100-line JS I think who will collapse. That's why PHP introduces a delimiter--at least for a large part of the reason.

The function of the 1.PHP delimiter is to follow the original, including the newline format, and output something inside it;
2. Any special characters in the PHP delimiter do not need to be escaped;
The PHP variable in the 3.PHP delimiter is replaced with its value as normal.

The delimiter format in PHP is this:

<<<Eof ... Eof;

Like what:

$url = ' http://baidu.com '; $js = <<<eof<script type= "text/javascript" >window. top.location.href = " $url? login "; </script>eof;//do not have any spaces before this Terminator Echo$js;

Use of the PHP delimiter EOF