PHP无限遍历数组

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<title>无限数组遍历</title>
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<?php

//生成从1到100的数组的值
$arr=array();
echo "<pre>"; //按原格式显示
for ($i=0;$i<=99;$i++){
$arr[$i]=($i+1);
}
print_r($arr);
echo "</pre>";

//无限遍历数组
$a1=array("a","b","c"); //一维数组
$a2=array(array(21,3,6),array("a","b","c")); //二维数组
$a3=array(array(array(5,55),4,444),2,7,6,8,array("w","d",array(3,2,"a"),"s")); //多维不规则数组

function fun($a){
      foreach($a as $val){
     if (is_array($val)){ //如果键值是数组，则进行函数递归调用
    fun($val);
  }
  else{ // 如果键值是数值，则进行输出
    echo "$val<br />";
  } //end if
   } //end foreach
} //end fun

fun($a3);

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