多为数组转换成一维递归

//静态变量是只存在于函数作用域中的变量，注释：执行后这种变量不会丢失（下次调用这个函数时，变量仍会记着原来的值）

function array_multi2single($array){

    static $result_array=array();

    foreach($array as $value){

        if(is_array($value)){

            array_multi2single($value);

        }

        else

        $result_array[]=$value;

    }

    return $result_array;

}



$array=array("1"=>array("A","B","C",array("D","E")),"2"=>array("F","G","H","I"));

$array=array_multi2single($array);

foreach($array as $value){

    echo "<h5>$value</h5>";

    echo "<br>";

}

//采用数组引用来实现，这样比上一种要好哦
function array_multi2single($array,&$rs = array()){
    foreach($array as $value){
        if(is_array($value)){
            array_multi2single($value, $rs);
        }
        else
        $rs[]=$value;
    }
}

$array=array("1"=>array("A","B","C",array("D","E")),"2"=>array("F","G","H","I"));
array_multi2single($array, $rs);

print_r($rs);