Question

我试图从一串RTTTL命令中捕获命令，如下所示：

 2a4, 2e, 2d#, 2b4, 2a4, 2c, 2d, 2a#4, 2e., e, 1f4, 1a4, 1d#, 2e., d, 2c., b4, 1a4, 1p, 2a4, 2e, 2d#, 2b4, 2a4, 2c, 2d, 2a#4, 2e., e, 1f4, 1a4, 1d#, 2e., d, 2c., b4, 1a4

我正在使用的正则表达式是(\S+),|$，全局和多行打开，正如我读到$在多行模式打开时匹配EOL，但是这不会发生，因此我不能捕获结束该行的最后一个命令1a4。所有其他命令都从该组中捕获。

我应该用什么正则表达式捕获最后一个命令？

Answer 1

只需添加一个前瞻或非捕获组，如下所示。并从组索引1中获取所需的字符串。

(\S+)(?:,|$)

DEMO

OR

(\S+)(?=,|$)

DEMO

使用前瞻时，您也不需要拥有捕获组。

\S+(?=,|$)

(?=,|$)正向前瞻声明匹配必须后跟,或行锚点的结尾。 \S+匹配一个或多个非空格字符。

Answer 2

另一种解决方案

$a = " 2a4, 2e, 2d#, 2b4, 2a4, 2c, 2d, 2a#4, 2e., e, 1f4, 1a4, 1d#, 2e., d, 2c., b4, 1a4, 1p, 2a4, 2e, 2d#, 2b4, 2a4, 2c, 2d, 2a#4, 2e., e, 1f4, 1a4, 1d#, 2e., d, 2c., b4, 1a4"; 
$r=explode(",",preg_replace("/\\s+/","",$a));
var_dump($r);

<强>输出：

array (size=37)
  0 => string '2a4' (length=3)
  1 => string '2e' (length=2)
  2 => string '2d#' (length=3)
  3 => string '2b4' (length=3)
  4 => string '2a4' (length=3)
  5 => string '2c' (length=2)
  6 => string '2d' (length=2)
  7 => string '2a#4' (length=4)
  8 => string '2e.' (length=3)
  9 => string 'e' (length=1)
  10 => string '1f4' (length=3)
  11 => string '1a4' (length=3)
  12 => string '1d#' (length=3)
  13 => string '2e.' (length=3)
  14 => string 'd' (length=1)
  15 => string '2c.' (length=3)
  16 => string 'b4' (length=2)
  17 => string '1a4' (length=3)
  18 => string '1p' (length=2)
  19 => string '2a4' (length=3)
  20 => string '2e' (length=2)
  21 => string '2d#' (length=3)
  22 => string '2b4' (length=3)
  23 => string '2a4' (length=3)
  24 => string '2c' (length=2)
  25 => string '2d' (length=2)
  26 => string '2a#4' (length=4)
  27 => string '2e.' (length=3)
  28 => string 'e' (length=1)
  29 => string '1f4' (length=3)
  30 => string '1a4' (length=3)
  31 => string '1d#' (length=3)
  32 => string '2e.' (length=3)
  33 => string 'd' (length=1)
  34 => string '2c.' (length=3)
  35 => string 'b4' (length=2)
  36 => string '1a4' (length=3)

匹配EOL角色？

2 个答案: