PHP 数据类型和判断变量类型

<meta charset="UTF-8">
<?php
$val1 = 1;
$val2 = 3.14;
$val3 = &#39;阅谁问君诵，水落清香浮。&#39;;
$val4 = array(&#39;aaa&#39;,&#39;bbb&#39;);
$val5 = true;
$val6 = function(){};
$val7 = null;
var_dump($val1);//整数
echo &#39;<br>&#39;;
var_dump($val2);//浮点数
echo &#39;<br>&#39;;
var_dump($val3);//字符串
echo &#39;<br>&#39;;
var_dump($val4);//数组
echo &#39;<br>&#39;;
var_dump($val5);//布尔
echo &#39;<br>&#39;;
var_dump($val6);//对象
echo &#39;<br>&#39;;
var_dump($val7);//NULL
?>