PHP數組foreach遍歷輸出例子詳解

2024-09-04 11:46:33

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通常我們對于數據遍歷會使用到foreach來操作當然也有使用到while list each函數來實現了,但在方便面上來看foreach更簡潔好用性能也非常的不錯,下面本人整理了一款在開發應用中foreach前后使用例子,希望對大家會有所幫助.

簡單的一個php數組函數,之前沒這個需要一直都不知道有這么一個函數,擦汗...

php數組逆序輸出代碼

foreach(array_reverse($array) AS $key=>$value){

echo $value.'

';

}

array_reverse (PHP 4, PHP 5)

array_reverse — 返回一個單元順序相反的數組

說明:array array_reverse ( array $array [, bool $preserve_keys ] )

array_reverse() 接受數組 array 作為輸入并返回一個單元為相反順序的新數組,如果 preserve_keys 為 TRUE 則保留原來的鍵名.

Example #1 array_reverse() 例子,代碼如下:

<?php

$input = array("php", 4.0, array("green", "red"));

$result = array_reverse($input);

$result_keyed = array_reverse($input, TRUE);

?>

這將使 $result 和 $result_keyed 具有相同的單元,但是注意鍵名的區別,$result 和 $result_keyed 的打印輸出顯示分別為:

Array

(

    [0] => Array

        (

            [0] => green

            [1] => red

        )

    [1] => 4

    [2] => php

)

Array

(

    [2] => Array

        (

            [0] => green

            [1] => red

        )

    [1] => 4

    [0] => php

)

例子,在PHP模板引擎中,模板文件:

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>{$web_tile}</title> //開源軟件:Vevb.com

</head>

<body>

{$article_title}

 

-- by {$author}

<hr/>

 

{$content}

 

-- publish @ {$time}

 

 

foreach test:

{foreach ( from=url key=b item=c )}

<a href="index.php?artcle_id={==b}">{==c}</a>

{/foreach}

 

</body>

</html>

解析引擎,代碼如下:

// var

 $pattern_var = "/{$left_tag}＼＼$([＼w＼d]+){$right_tag}/";

 $replace_var = '<?php echo ＼$this->var_tpl_arr["$1"];?>';



 if (preg_match($pattern_var, $content)) {

 $content = preg_replace($pattern_var, $replace_var, $content);

 }



 // foreach

 preg_match_all("/{$left_tag}foreach＼s+([^{]+?){$right_tag}/is", $content, $match_foreach);

 if (isset($match_foreach[1]) && is_array($match_foreach)) {

 foreach($match_foreach[1] as $match_key => $match_value) {

 $split_foreachs = array_filter(preg_split('/＼s+/is', $match_value));

 $new_foreach_tag = array();

 foreach($split_foreachs as $split_foreach) {

 $split = explode("=", $split_foreach);

 if (count($split == 2)) {

 if(in_array($split[0], array("from","item","key"))) {

//過濾標簽不存在過濾

 $new_foreach_tag[$split[0]] = $split[1];

 }

 }

 }



 $from = $key = $item = '';

 extract($new_foreach_tag);

 $key = ($key) ? '$'.$key.' =>' : '' ;

 $replace_foreach = '<?php foreach($this->var_tpl_arr["'.$from.'"] as '.$key.' $'.$item.') { ?>';

 $content = str_replace($match_foreach[0][$match_key], $replace_foreach, $content);



 }

 }



 $pattern_foreach = "/{$left_tag}＼/foreach{$right_tag}/";

 $replace_foreach = "<?php } ?>";

 if (preg_match($pattern_foreach, $content)) {

 $content = preg_replace($pattern_foreach, $replace_foreach, $content);

 }



 // var in statement

 $pattern_var = "/{$left_tag}==([＼w＼d]+){$right_tag}/";

 $replace_var = '<?php echo ＼$$1;?>';



 if (preg_match($pattern_var, $content)) {

 $content = preg_replace($pattern_var, $replace_var, $content);

 }

解析后代碼如下:

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title><?php echo $this->var_tpl_arr["web_tile"];?></title>

</head>

<body>

<?php echo $this->var_tpl_arr["article_title"];?>

 

-- by <?php echo $this->var_tpl_arr["author"];?>

<hr/>

 

<?php echo $this->var_tpl_arr["content"];?>

 

-- publish @ <?php echo $this->var_tpl_arr["time"];?>

 

 

foreach test:

<?php foreach($this->var_tpl_arr["url"] as $b => $c) { ?>

<a href="index.php?artcle_id=<?php echo $b;?>"><?php echo $c;?></a>

<?php } ?>

 

</body>

</html>

使用代碼如下:

<?php

require_once 'core/YATP.class.php';

$app = new YATP();

date_default_timezone_set("Asia/Shanghai");

$app->is_cache = false;

$article_title = "yet,it is a simple template engine";

$author = "sanwhiteyu@tencent.com";

$web_tile = "just test ";

$content = "It is easy to write a simple template engine for yourself,what u can do is try to do it!";

$time = date("Y-m-d H:i:s",time());

$url = array(

"url1"=>"http://www.49028c.com",

"url2"=>"http://www.49028c.com",

);

$app->assign("article_title",$article_title);

$app->assign("author",$author);

$app->assign("web_tile",$web_tile);

$app->assign("content",$content);

$app->assign("time",$time);

$app->assign("url",$url);

$app->display("index.html");

// end of script

?>