php 如何用 <br/> 替换换行符或 \r\n？
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How to replace newline or \r\n with <br/>?
提问by Thomas McCabe
Trying to simply replace some new lines. Have tried 3 different ways and I get no change:
试图简单地替换一些新行。尝试了 3 种不同的方法，但没有任何变化：
$description = preg_replace('/\r?\n|\r/','<br/>', $description);
$description = str_replace(array("\r\n","\r","\n"),"<br/>", $description);
$description = nl2br($description);
These should all work but I still get the newlines. They are double: "\r\r". That shouldn't make any of these fail right?
这些都应该有效，但我仍然得到换行符。它们是双重的：“\r\r”。这不应该使任何这些失败，对吗？
回答by Robik
There is already nl2br()function that replacesinserts<br>tags before new line characters:
已经有一个nl2br()功能可以在换行符之前替换插入<br>标签：
Example (codepad):
示例（键盘）：
<?php
// Won't work
$desc = 'Line one\nline two';
// Should work
$desc2 = "Line one\nline two";
echo nl2br($desc);
echo '<br/>';
echo nl2br($desc2);
?>
But if it is still not working make sure the text $desciptionis double-quoted.
但如果它仍然不起作用，请确保文本$desciption是双引号的。
That's because single quotes do not 'expand' escape sequences such as \ncomparing to double quoted strings. Quote from PHP documentation:
这是因为单引号不会“扩展”转义序列，例如\n与双引号字符串进行比较。引用自 PHP 文档：
Note: Unlike the double-quoted and heredoc syntaxes, variables and escape sequences for special characters will not be expanded when they occur in single quoted strings.
注意：与双引号和heredoc 语法不同，特殊字符的变量和转义序列在出现在单引号字符串中时不会被扩展。
回答by afarazit
Try using this
尝试使用这个
$description = preg_replace("/\r\n|\r|\n/",'<br/>',$description);
回答by regilero
You may have real characters "\" in the string (the single quote strings, as said @Robik).
字符串中可能有真正的字符“\”（单引号字符串，如@Robik 所说）。
If you are quite sure the '\r' or '\n' strings should be replaced as well, I'm not talking of special characters here but a sequence of two chars '\' and 'r', then escape the '\' in the replace string and it will work:
如果您非常确定 '\r' 或 '\n' 字符串也应该被替换，我在这里不是在谈论特殊字符，而是在谈论两个字符 '\' 和 'r' 的序列，然后转义 '\ ' 在替换字符串中，它将起作用：
str_replace(array("\r\n","\r","\n","\r","\n","\r\n"),"<br/>",$description);
回答by sakatc
nl2br()as you have it should work fine:
nl2br()正如你所拥有的，它应该可以正常工作：
$description = nl2br($description);
It's more likely that the unclosed 'on the first line of your example code is causing your issue. Remove the ' after $description...
'示例代码第一行的未关闭更有可能导致您的问题。删除 $description 之后的 '...
...$description');
回答by infografnet
nl2br() worked for me, but I needed to wrap variable with double quotes:
nl2br() 对我有用，但我需要用双引号包裹变量：
This works:
这有效：
$description = nl2br("$description");
This doesn't work:
这不起作用：
$description = nl2br($description);
回答by l2aelba
Try this:
尝试这个：
echo str_replace( array('\r\n','\n\r','\n','\r'), '<br>' , $description );
回答by Radeck
This will work for sure:
这肯定会起作用：
str_replace("\r","<br />",$description);
str_replace("\n","<br />",$description);
回答by softcod.com
$description = nl2br(stripcslashes($description));
回答by Dipak Chatterjee
I think str_replace(array("\r\n", "\r", "\n"), " ", $string); Will work.
我认为 str_replace(array("\r\n", "\r", "\n"), " ", $string); 将工作。
回答by Evgeniy Skulditsky
If you are using nl2brall occurrences of \nand \rwill be replaced by <br>. But if (i dont know how it is) you still get new lines you can use
如果您使用nl2br所有出现的\n和\r将被替换为<br>。但是如果（我不知道它是怎么回事）你仍然可以使用新的线路
str_replace("\r","",$description);
str_replace("\n","",$description);
To replase unnecessary new lines by empty string
用空字符串替换不必要的新行
