[liangdong@bb-browser-test00.vm.baidu.com php_project]$ cat main.php 
<?php
function make_variables($prefix, $start, $end) {
        while ($start <= $end) {
                $var_name = $prefix . $start;
                global $$var_name;
                ++ $start;
        }
}

make_variables('var', 1, 7);
for ($i = 1; $i <= 7; ++ $i) {
        $var_name = 'var' . $i;
        echo $$var_name;
}
?>