With JavaScript regular expression replace, trying to replace anything between <head> and </head> tags so that:
<head>
Multiline foo
</head>
<body>
Multi line bar
</body>
gets replaced into:
<body>
Multi line bar
</body>
and trying with the very basic: <head(.*)\/head>/m which doesn't work. It works fine when line breaks are removed from string. No matter what type of line breaks, what's the magic?
With JavaScript regular expression replace, trying to replace anything between <head> and </head> tags so that:
<head>
Multiline foo
</head>
<body>
Multi line bar
</body>
gets replaced into:
<body>
Multi line bar
</body>
and trying with the very basic: <head(.*)\/head>/m which doesn't work. It works fine when line breaks are removed from string. No matter what type of line breaks, what's the magic?
- see blog.stevenlevithan./archives/singleline-multiline-confusing – endolith Commented Jun 7, 2012 at 19:25
2 Answers
Reset to default 8The problem is that the dot metacharacter doesn't match newlines. In most regex flavors you can force it to match everything by setting "DOTALL" or "single-line" mode, but JavaScript doesn't support that. Instead, you have to replace the dot with something that does match everything. The most mon idiom is [\s\S] ("any whitespace character or any character that's not whitespace").
Alan is right, to summarize, use /<head([\s\S]*)\/head>/ and it should do what you wish.
The actual regex i'd use for the job is /<head>([\s\S]*?)<\/head>/ but the difference probably won't matter, since it just assures there is no greedy matching with a 2nd head tag that should never be there :)