PHP about the usage of <<<

YUN77.NET Hong Kong server free trial welcome to visit~~~

Heredoc technology is generally not described in detail in formal PHP documents and technical books. It is only mentioned that it is a Perl-style string output technology. However, some current forum programs and some article systems cleverly use heredoc technology to partially realize the quasi-separation of interface and code. The phpwind template is a typical example.
As follows:
$name = 'Shallow water swimming';
print <<






Hello, $name!


EOT;
?>
1. Start with the << 2. Variables located between the start tag and the end tag can be parsed normally, but functions cannot. In heredoc, variables do not need to be spliced ​​with connectors. or,, as follows:
$v=2;
$a= << "abc"$v
"123"
EOF;
echo $a; //The result is output together with double quotes: "abc"2 "123"
3. Heredoc is often used when outputting documents containing a large number of HTML syntax documents. For example: the function outputhtml() should output the HTML homepage. There are two ways to write it. Obviously the second way of writing is simpler and easier to read.
function outputhtml(){
echo "";
echo "";
echo "Homepage content";
echo ";
}
function outputhtml()
{
echo <<

Homepage content

EOT;
}
outputhtml();