通过PHP将自定义脚本标记转换为带有锚标记的新脚本

Question

I need some help with converting a string in PHP. I've been trying to do this for hours but I can only seem to convert simple scripts with str_replace().

I'm trying to convert the custom script below:

<start=0:03>Line one goes here<end=0:09>
<start=0:09>Line two goes here<end=0:12>
<start=0:20>Line three goes here<end=0:26>
<start=0:32>Line four goes here<end=0:42>

Into a new script with anchor tags like this:

<a href="?start=0:03&end=0:09">Line one goes here</a>
<a href="?start=0:09&end=0:12">Line two goes here</a>
<a href="?start=0:20&end=0:26">Line three goes here</a>
<a href="?start=0:32&end=0:42">Line four goes here</a>

Can anyone help please?

Thank you.

Answer 1

For this kind of a little elaborate search/replacement, the most handy is to use a regex pattern with preg_replace:

$re = '/<(start=\d+:\d+)(>.*?<)(end=\d+:\d+)>/s';
$subst = '<a href="?$1&$3$2/a>';
$result = preg_replace($re, $subst, $yourstring);

pattern details:

/                  # pattern delimiter
<                  # literal <
(start=\d+:\d+)    # group 1: literal "start=", one or more digits,
                   # literal ":" and one or more digits
(>.*?<)            # group 2: literal >, all characters until <, that must be followed 
(end=\d+:\d+>)     # by capture the group 3
/s                 # pattern delimiter, and s modifier

By default the . matches all characters except the newline character, the s modifier allows it to match newlines too.

replacement:

$1, $2, $3 refers to the content captured by the groups