PHP recursive usage and recursive directory examples

PHP recursive usage and recursive directory examples_PHP tutorial

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Release： 2016-07-13 10:48:04

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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...