php Warning:strstr()[function.strstr]:Empty delimiter

Warning: strstr() [function.strstr]: Empty delimiter,非常奇怪,难道php函数strstr的某个参数出问题了?,于是写了个测试的例子:

  1. <?php
  2. $text=”asdfghjklqwertyuiopzxcvbnm”;
  3. //$key=”g”;
  4. //根据php错误提示Empty delimiter,判断应该不会是$text的值出问题,所以故意注释了key值
  5. if(strstr($text, $key)){
  6. echo “found it”;
  7. }else{
  8. echo “not found”;
  9. }
  10. ?>

strstr()竟然不报错,于是想到$key值可能会是空串”",姑且一试,果然strstr($text,”")时,提示出错Warning: strstr() [function.strstr]: Empty delimiter