推荐:yahoo的php面试题

呵呵，翻译了篇东西，N长时间没用英语了，出了丑大家可一定要指出来啊。翻译自：Nick Halstead's Blog
A friend recently got some pre-interview questions from YAHOO for a PHP
job. Following up my previous post about programmer questions I
thought I would post them to give people examples of what a large
corporation like YAHOO asks.
最近一位朋友得到了Yahoo的一些PHP面试题目，依照我之前发表关于程序员的相关文章的原则，我想我应该在这里发布出来，以给读者朋友们提供一些例
子，让大家看看像YAHOO这样的大公司关心哪些问题。
1. Which of the following will not add john to the users array?
1、下面哪个选项没有将 john 添加到users 数组中？
         1. $users[] = ‘john’;
         2. array_add($users,’john’);
         3. array_push($users,‘john’);
         4. $users ||= ‘john’;
2. What’s the difference between sort(), assort() and ksort? Under what
circumstances would you use each of these?
2、sort(), asort()(注：原作者为assort,应该是笔误)和ksort()
三者之间有什么差别？你分别在什么情况下会使用上面三个函数？
3. What would the following code print to the browser? Why?
3、下面这段代码将在浏览器上打印出什么内容？为什么？
      $num = 10;
      function multiply(){
            $num = $num * 10;
      }
      multiply();
      echo $num;
4. What is the difference between a reference and a regular variable?
How do you pass by reference & why would you want to?
4、引用变量与普通变量之间有何区别？如何通过引用传值？在什么情况下会这样做？
5. What functions can you use to add library code to the currently
running script?
5、哪些函数可以被用来向当前的代码中添加库代码？
6. What is the difference between foo() & @foo()?
6、foo()和@foo