i have a file in this format
string: string1
string: string2
string: string3
i want to split the lines by space
and :
,so initially i wrote this:
my @array = split(/[:\s]/,$lineOfFile);
the result wasn't as expected, because inside @array
the split
inserts also white space
, so after some researches i understood that i have to escape the \\s
so i wrote
my @array = split(/[:\\s]/,$lineOfFile);
why i have to escape \\s
, the character :
isn't a special character or not?
can someone explain me that?
thanks in advance.
You do not need to double escape \\s
and the colon is not a character of special meaning. But in your case, it makes sense to avoid using a character class altogether and split on a colon followed by whitespace "one or more" times.
my @array = split(/:\s+/, $lineOfFile);
You don't have to double up the backslash. Have you tried it?
split /[:\\s]/, $line
will split on a colon :
or a backslash \\
or a small S s
, giving
("", "tring", " ", "tring1")
which isn't what you want at all. I suggest you split on a colon followed by zero or more spaces
my @fields = split /:\s*/, $line
which gives this result
("string", "string1")
which I think is what you want.
The problem is, that /[:\\s]/
only searches for a single character. Thus, when applying this regex, you get something like
print $array[0], ' - ', $array[1], ' - ', $array[2];
string - - string1
because it splits between :
and the whitespace before string1
. The string string: string1
is therefore splitted into three parts, string
, the empty place between :
and the whitespace and string1
. However, allowing more characters
my @array = split(/[:\s]+/,$lineOfFile);
works well, since :
+whitespace is used for splitting.
print $array[0], ' - ', $array[1];
string - string1
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.