PHP recursive usage and recursive directory examples

PHP recursive usage and recursive directory examples_PHP tutorial

WBOY

Release： 2016-07-13 10:48:04

Original

1197 people have browsed it

In PHP, the recursive algorithm is one of the few data traversal methods we have. Let me introduce to you some useful things using recursion.

Look at a simple recursion example

Example 1

if($a > 1){

The code is as follows

代码如下

复制代码

function demo($a) {

static $sum=1;

if($a > 1){

$sum*=$a;

demo(--$a);

}else{

$a=$sum;

}

return $sum;

}

echo demo(10);

Copy code

function demo($a) {

代码如下

复制代码

class listdir{
var $depth;
var $dirname;
var $list;
var $tostring;

function listdir($dir){
$this->dirname=$dir;
$this->depth=0;
$this->tostring=”";
}

//把结果保存进多维数组
function getlist($dir=”"){
if($dir==”")$dir=$this->dirname;
$d=@dir($dir);
while(false!==($item=$d->read()))
{
if($item!=”.”&&$item!=”..”)
{
$path=$dir.”/”.$item;
if(is_dir($path)){
$this->depth+=1;
$this->getlist($path);
}else{
$this->list[$this->depth][]=$item;
}
}
}
$this->list[$this->depth]['directory']=$dir;
$this->depth-=1;
$d->close();
return $this->list;
}

//字符窜化结果

function tostring($dir=”"){
if($dir==”")$dir=$this->dirname;
$d=@dir($dir);
$this->tostring.=”

”.$item.”

n”;
return $this->tostring;
}
}
$wapdir=”jquery”;
$d=new listdir($wapdir);
echo $d->tostring();
?>

输出结果：

jquery-1.3.2.js

jquery-1.3.2.min.js

jquery-1.3.2-vsdoc2.js

test.html

common.js

common.js

jquery-1.3.2.js

static $sum=1;

$sum*=$a;

Example 2 Traverse directories

The code is as follows

Copy code

class listdir{
var $depth;
var $dirname;
var $list;
var $tostring;<🎜> <🎜>function listdir($dir){
$this->dirname=$dir;
$this->depth=0;
$this->tostring=””;
} //Save the result into a multi-dimensional array
function getlist($dir=""){
if($dir==”")$dir=$this->dirname;
$d=@dir($dir);
while(false!==($item=$d->read()))
{
if($item!=”.”&&$item!=”..”)
{
$path=$dir.”/”.$item;
if(is_dir($path)){
$this->depth+=1;
$this->getlist($path);
}else{
$this->list[$this->depth][]=$item;
}
}
}
$this->list[$this->depth]['directory']=$dir;
$this->depth-=1;
$d->close();
return $this->list;
} //Character channeling result function tostring($dir=""){
if($dir==”")$dir=$this->dirname;
$d=@dir($dir);
$this->tostring.=”

”.$item.”

n”;
return $this->tostring;
}
}
$wapdir=”jquery”;
$d=new listdir($wapdir);
echo $d->tostring();
?> Output result:

jquery-1.3.2.js

jquery-1.3.2.min.js

jquery-1.3.2-vsdoc2.js

test.html

common.js

common.js

jquery-1.3.2.js

http://www.bkjia.com/PHPjc/632807.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/632807.htmlTechArticleIn php, the recursive algorithm is a data traversal method that we can’t compare with. Let me tell you about it below. Let’s introduce some useful things using recursion. Look at a simple recursion example...