块级作用域

 1 <script>
 2     if(1==1)
 3     {
 4         var wa = 456;
 5     }
 6     console.log(wa);
 7 
 8     if(TRUE)
 9     {
10         var va = 456;
11     }
12     console.log(va);
13 </script>
14 <?php
15 /**
16  * Created by PhpStorm.
17  * User: Administrator
18  * Date: 2016/10/6
19  * Time: 22:34
20 */
21 
22 
23 if(TRUE)
24 {
25     $var = 123;
26 }
27 var_dump($var);