3 ways to split a string into a slice

Split on comma or other substring

Use the strings.Split function to split a string into its comma separated values.

s := strings.Split("a,b,c", ",")
fmt.Println(s)
// Output: [a b c]

To include the separators, use strings.SplitAfter. To split only the first n values, use strings.SplitN and strings.SplitAfterN.

You can use strings.TrimSpace to strip leading and trailing whitespace from the resulting strings.

Split by whitespace and newline

Use the strings.Fields function to split a string into substrings removing any space characters, including newlines.

s := strings.Fields(" a \t b \n")
fmt.Println(s)
// Output: [a b]

Split on regular expression

In more complicated situations, the regexp Split method might do the trick.

It splits a string into substrings separated by a regular expression. The method takes an integer argument n; if n >= 0, it returns at most n substrings.

a := regexp.MustCompile(`a`)              // a single `a`
fmt.Printf("%q\n", a.Split("banana", -1)) // ["b" "n" "n" ""]
fmt.Printf("%q\n", a.Split("banana", 0))  // [] (nil slice)
fmt.Printf("%q\n", a.Split("banana", 1))  // ["banana"]
fmt.Printf("%q\n", a.Split("banana", 2))  // ["b" "nana"]

zp := regexp.MustCompile(` *, *`)             // spaces and one comma
fmt.Printf("%q\n", zp.Split("a,b ,  c ", -1)) // ["a" "b" "c "]

See this Regexp tutorial and cheat sheet for a gentle introduction to the Go regexp package with plenty of examples.

Further reading

40+ practical string tips [cheat sheet]

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