PHP数组foreach遍历输出例子详解
通常我们对于数据遍历会使用到foreach来操作当然也有使用到while list each函数来实现了,但在方便面上来看foreach更简洁好用性能也非常的不错,下面本人整理了一款在开发应用中foreach前后使用例子,希望对大家会有所帮助.
简单的一个php数组函数,之前没这个需要一直都不知道有这么一个函数,擦汗...
php数组逆序输出代码
- foreach(array_reverse($array) AS $key=>$value){
- echo $value.'
- ';
- }
array_reverse (PHP 4, PHP 5)
array_reverse — 返回一个单元顺序相反的数组
说明:array array_reverse ( array $array [, bool $preserve_keys ] )
array_reverse() 接受数组 array 作为输入并返回一个单元为相反顺序的新数组,如果 preserve_keys 为 TRUE 则保留原来的键名.
Example #1 array_reverse() 例子,代码如下:
- <?php
- $input = array("php", 4.0, array("green", "red"));
- $result = array_reverse($input);
- $result_keyed = array_reverse($input, TRUE);
- ?>
这将使 $result 和 $result_keyed 具有相同的单元,但是注意键名的区别,$result 和 $result_keyed 的打印输出显示分别为:
- Array
- (
- [0] => Array
- (
- [0] => green
- [1] => red
- )
- [1] => 4
- [2] => php
- )
- Array
- (
- [2] => Array
- (
- [0] => green
- [1] => red
- )
- [1] => 4
- [0] => php
- )
例子,在PHP模板引擎中,模板文件:
- <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
- <html>
- <head>
- <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
- <title>{$web_tile}</title> //开源软件:phpfensi.com
- </head>
- <body>
- {$article_title}
- <br/>
- -- by {$author}
- <hr/>
- <br/>
- {$content}
- <br/>
- -- publish @ {$time}
- <br/>
- <br/>
- foreach test:
- {foreach ( from=url key=b item=c )}
- <a href="index.php?artcle_>{==c}</a>
- {/foreach}
- <br/>
- </body>
- </html>
解析引擎,代码如下:
- // 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"))) {
- //过滤标签 不存在过滤
- $new_foreach_tag[$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);
- }
解析后代码如下:
- <!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"];?>
- <br/>
- -- by <?php echo $this->var_tpl_arr["author"];?>
- <hr/>
- <br/>
- <?php echo $this->var_tpl_arr["content"];?>
- <br/>
- -- publish @ <?php echo $this->var_tpl_arr["time"];?>
- <br/>
- <br/>
- foreach test:
- <?php foreach($this->var_tpl_arr["url"] as $b => $c) { ?>
- <a href="index.php?artcle_><?php echo $c;?></a>
- <?php } ?>
- <br/>
- </body>
- </html>
使用代码如下:
- <?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.phpfensi.com",
- "url2"=>"http://www.phpfensi.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
- ?>