如果存在,我需要刪除\r\n\r\n
在字符串的最開始和/或最後。php正則表達式 - 刪除 r n r n在最開始和最後一個字符串
我的問題是我無法實現我的目標代碼如下。
//if exists, remove \r\n\r\n at the very beginning
$str = preg_replace('/^(\r\n\r\n)/', '', $str);
//if exists, remove \r\n\r\n at the very end
$str = preg_replace('/$(\r\n\r\n)/', '', $str);
也許我的html輸出的源代碼視圖可以給你一些線索。我不知道原因,但<br />
標籤不是並排的。他們的位置是一個一個在另一個之下。
<br />
<br />
some text
...
...
some text<br />
<br />
還在下面,我分享我的整個字符串操作代碼。我有問題的2行代碼是以下代碼的一部分。 (除了上述2行代碼以外的其他部分效果良好)
function convert_str ($str)
{
// remove excess whitespace
// looks for a one or more spaces and replaces them all with a single space.
$str = preg_replace('/ +/', ' ', $str);
// check for instances of more than two line breaks in a row
// and then change them to a total of two line breaks
$str = preg_replace('/(?:(?:\r\n|\r|\n)\s*){2}/s', "\r\n\r\n", $str);
//if exists, remove \r\n\r\n at the very beginning
$str = preg_replace('/^(\r\n\r\n)/', '', $str);
//if exists, remove \r\n\r\n at the very end
$str = preg_replace('/$(\r\n\r\n)/', '', $str);
//if exists, remove 1 space character just before any \r\n
$str = str_replace(" \r\n", "\r\n", $str);
//if exists, remove 1 space character just after any \r\n
$str = str_replace("\r\n ", "\r\n", $str);
// if exists; remove 1 space character just before punctuations below:
// $punc = array('.',',',';',':','...','?','!','-','—','/','\\','「','」','‘','’','"','\'','(',')','[',']','’','{','}','*','&','#','^','<','>','|');
$punc = array(' .',' ,',' ;',' :',' ...',' ?',' !',' -',' —',' /',' \\',' 「',' 」',' ‘',' ’',' "',' \'',' (',')',' [',' ]',' ’',' {',' }',' *',' &',' #',' ^',' <',' >',' |');
$replace = array('.',',',';',':','...','?','!','-','—','/','\\','「','」','‘','’','"','\'','(',')','[',']','’','{','}','*','&','#','^','<','>','|');
$str = str_replace($punc,$replace,$str);
return $str;
}
請問您能糾正我嗎?
感謝
BR
你知道[**修剪**]( http://php.net/manual/en/function.trim.php)對不對? – elclanrs 2013-04-10 06:55:14
@elclanrs我錯誤的堅持使用preg_replace讓我盲目,我認爲,直到修剪提到的答案。我感到羞愧。非常感謝。你的評論對我來說是一個很好的教訓。 – 2013-04-10 07:03:07
也使用正則表達式的字符串,這很容易是非常糟糕的! – ITroubs 2013-04-10 07:03:30