用 PHP 修剪前导空白？
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Trim leading white space with PHP?
提问by markratledge
There seems to be a bug in a Wordpress PHP function that leaves whitespace in front of the title of the page generated by <?php echo wp_title(''); ?>I've been through the Wordpress docs and forums on that function without any luck.
Wordpress PHP 函数中似乎存在一个错误，它在生成的页面标题前留下空白，<?php echo wp_title(''); ?>我已经浏览了有关该函数的 Wordpress 文档和论坛，但没有任何运气。
I'm using it this way <body id="<?php echo wp_title(''); ?>">in order to generate an HTML body tag with the id of the page title.
我以这种方式使用它<body id="<?php echo wp_title(''); ?>">是为了生成一个带有页面标题 id 的 HTML body 标记。
So what I need to do is strip that white space, so that the body tag looks like this <body id="mypage">instead of this <body id=" mypage">
所以我需要做的是去掉那个空白区域，让 body 标签看起来像这样<body id="mypage">而不是这样<body id=" mypage">
The extra white space kills the CSS I'm trying to use to highlight menu items of the active page. When I manually add a correct body tag without the white space, my CSS works.
多余的空白会杀死我试图用来突出显示活动页面菜单项的 CSS。当我手动添加没有空格的正确 body 标记时，我的 CSS 可以工作。
So how would I strip the white space? Thanks, Mark
那么我将如何去除空白？谢谢，马克
Part Two of the Epic
史诗的第二部分
John, A hex dump was a good idea; it shows the white space as two "20" spaces. But all solutions that strip leading spaces and white space didn't.
约翰，十六进制转储是个好主意；它将空白显示为两个“20”空格。但是所有去除前导空格和空白的解决方案都没有。
And, <?php ob_start(); $title = wp_title(''); ob_end_clean(); echo $title; ?>
和， <?php ob_start(); $title = wp_title(''); ob_end_clean(); echo $title; ?>
gives me < body id ="">
给我 < body id ="">
and <?php ob_start(); $title = wp_title(''); echo $title; ?>
和 <?php ob_start(); $title = wp_title(''); echo $title; ?>
gives me < body id =" mypage">
给我 < body id =" mypage">
Puzzle. The root of the problem is that wp_title has optional page title leading characters - that look like chevrons - that are supposed to be dropped when the option is false, and they are, but white space gets dumped in.
谜。The root of the problem is that wp_title has optional page title leading characters - that look like chevrons - that are supposed to be dropped when the option is false, and they are, but white space gets dumped in.
Is there a nuclear option?
有核选项吗？
Yup, tried them both before; they still return two leading spaces... arrgg
是的，之前都试过；他们仍然返回两个前导空格... arrgg
回答by John Kugelman
Strip all whitespace from the left end of the title:
<?php echo ltrim(wp_title('')); ?>Strip all whitespace from either end:
<?php echo trim(wp_title('')); ?>Strip all spaces from the left end of the title:
<?php echo ltrim(wp_title(''), ' '); ?>Remove the first space, even if it's not the first character:
<?php echo str_replace(' ', '', wp_title(''), 1); ?>Strip only a single space (not newline, not tab) at the beginning:
<?php echo preg_replace('/^ /', '', wp_title('')); ?>Strip the first character, whatever it is:
<?php echo substr(wp_title(''), 1); ?>
去除标题左端的所有空格：
<?php echo ltrim(wp_title('')); ?>从任一端去除所有空格：
<?php echo trim(wp_title('')); ?>去掉标题左端的所有空格：
<?php echo ltrim(wp_title(''), ' '); ?>删除第一个空格，即使它不是第一个字符：
<?php echo str_replace(' ', '', wp_title(''), 1); ?>在开头只去掉一个空格（不是换行符，不是制表符）：
<?php echo preg_replace('/^ /', '', wp_title('')); ?>去掉第一个字符，不管它是什么：
<?php echo substr(wp_title(''), 1); ?>
Update
更新
From the Wordpress documentation on wp_title, it appears that wp_titledisplays the title itself unless you pass falsefor the second parameter, in which case it returns it. So try:
从 上的 Wordpress文档中wp_title，wp_title除非您传递false第二个参数，否则它似乎会显示标题本身，在这种情况下它会返回它。所以尝试：
<?php echo trim(wp_title('', false)); ?>
回答by mpen
ltrim($str)
回答by Chris Thompson
回答by Tomdkat
Thanks for this info! I was in the same boat in that I needed to generate page ids for CSS purposes based on the page title and the above solution worked beautifully.
感谢您提供此信息！我在同一条船上，因为我需要根据页面标题为 CSS 目的生成页面 id，并且上述解决方案工作得很好。
I ended up having an additional hurdle in that some pages have titles with embedded spaces, so I ended up coding this:
我最终遇到了一个额外的障碍，因为有些页面的标题带有嵌入的空格，因此我最终编写了以下代码：
<?php echo str_replace(' ','-',trim(wp_title('',false))); ?>
回答by james
add this to your functions.php
将此添加到您的functions.php
add_filter('wp_title', create_function('$a, $b','return str_replace(" $b ","",$a);'), 10, 2);
should work like a charm
应该像魅力一样工作
