如何将输出html存储到php中的var？

Question

how to store output html to an var in php ?

how to set $a = require(xx.php)?
the xx.php outputs html , i want to store this html to a var , how to do?
please see my codes bellow:

a.php codes:

<?php
    // a.php
    echo 'hello world';
?>

b.php

<pre>
<?php
    ob_start();
    $a=require('a.php');
    ob_clean();
    echo $a;    // get '1' but not 'hello world'

    // can not post , why?
    // can not post , why?
    // can not post , why?
    // can not post , why?
    // can not post , why?
    // can not post , why?

?>

Answer 1

The result of the "require" is not what you want. Try:

ob_start();
require('a.php');
$a = ob_get_clean();
echo $a;