How to split a delimited string in Ruby and conver

问题:

I have a string

"1,2,3,4"

and I'd like to convert it into an array:

[1,2,3,4]

How?

回答1:

>> "1,2,3,4".split(",")
=> ["1", "2", "3", "4"]

Or for integers:

>> "1,2,3,4".split(",").map { |s| s.to_i }
=> [1, 2, 3, 4]

Or for later versions of ruby (>= 1.9 - as pointed out by Alex):

>> "1,2,3,4".split(",").map(&:to_i)
=> [1, 2, 3, 4]

回答2:

"1,2,3,4".split(",") as strings

"1,2,3,4".split(",").map { |s| s.to_i } as integers

回答3:

For String Integer without space as String

arr = "12345"

arr.split('')

output: ["1","2","3","4","5"]

For String Integer with space as String

arr = "1 2 3 4 5"

arr.split(' ')

output: ["1","2","3","4","5"]

For String Integer without space as Integer

arr = "12345"

arr.split('').map(&:to_i)

output: [1,2,3,4,5]

For String

arr = "abc"

arr.split('')

output: ["a","b","c"]

Explanation:

1. arr -> string which you're going to perform any action.
2. split() -> is an method, which split the input and store it as array.
3. '' or ' ' or ',' -> is an value, which is needed to be removed from given string.

回答4:

the simplest way to convert a string that has a delimiter like a comma is just to use the split method

"1,2,3,4".split(',') # "1", "2", "3", "4"]

you can find more info on how to use the split method in the ruby docs

Divides str into substrings based on a delimiter, returning an array of these substrings.

If pattern is a String, then its contents are used as the delimiter when splitting str. If pattern is a single space, str is split on whitespace, with leading whitespace and runs of contiguous whitespace characters ignored.

If pattern is a Regexp, str is divided where the pattern matches. Whenever the pattern matches a zero-length string, str is split into individual characters. If pattern contains groups, the respective matches will be returned in the array as well.

If pattern is omitted, the value of $; is used. If $; is nil (which is the default), str is split on whitespace as if ` ‘ were specified.

If the limit parameter is omitted, trailing null fields are suppressed. If limit is a positive number, at most that number of fields will be returned (if limit is 1, the entire string is returned as the only entry in an array). If negative, there is no limit to the number of fields returned, and trailing null fields are not suppressed.

回答5:

"12345".each_char.map(&:to_i)

each_char does basically the same as split(''): It splits a string into an array of its characters.

hmmm, I just realize now that in the original question the string contains commas, so my answer is not really helpful ;-(..