Question

我想问一个与上一个问题（Remove new lines from string）略有不同的变化：

我想删除字符串中的新行，除了，当新行上的文本前面有一个空格“”时（这表示这是一个新的段落。这是一个例子：

   This is the first bit of text. It continues for a while until
there is a line break. It then continues for a bit longer but 
the line break also continues alongside it. 
   What you see here is the second paragraph. You'll notice that 
there is a space to mark the beginning of the paragraph. However
When joining these lines, a computer may not realize that the next
paragraph exists in this way.

Answer 1

$result = preg_replace('/\n++(?! )/', ' ', $subject);

正是如此。

<强>说明：

\n++  # Match one or more newlines; don't backtrack
(?! ) # only if it's impossible to match a space afterwards

Answer 2

按终点字符分解文本（使用PHP_EOL常量）并使用trim。

$lines = explode(PHP_EOL,$text);
$lines = array_map(function($line){
    return trim($line);
},$lines);
$text = implode(PHP_EOL,$lines);

// or if you are not familiar w/ array_map, simple use foreach
$lines = array();
foreach(explode(PHP_EOL,$text) as $line)
     $lines[] = trim($line);
$text = implode(PHP_EOL,$lines);

Answer 3

在您的文件中看起来像嵌入式小端BOM。

必须删除它们或在没有它们的情况下重写文件。

您可以使用像\xFF\xFE这样的正则表达式删除它们。

以下是十六进制编辑器中文本的一部分。

 00 61 00 6C 00 6F 00 6E 00 67 00 73 00 69 00 64 
 00 65 00 20 00 69 00 74 00 2E 00 20 00 0D 00 20 
 00 FF FE 20 00 FF FE 20 00 FF FE 57 00 68 00 61 
 00 74 00 20 00 79 00 6F 00 75 00 


 alongside it. 
    What you

从字符串中删除新行，并检查新段落中的空格（PHP）

3 个答案: