String Functions

The standard library’s strings package provides many useful string-related functions. Here are some examples to give you a sense of the package.

package main

import (
    "fmt"
    s "strings"
)

// We alias fmt.Println to a shorter name as we’ll use it a lot below.
var p = fmt.Println

func main() {

    // Here’s a sample of the functions available in strings.
    // Since these are functions from the package
    // not methods on the string object itself
    // we need pass the string in question as the first argument to the function.
    // You can find more functions in the strings package docs.
    p("Contains:  ", s.Contains("test", "es"))
    p("Count:     ", s.Count("test", "t"))
    p("HasPrefix: ", s.HasPrefix("test", "te"))
    p("HasSuffix: ", s.HasSuffix("test", "st"))
    p("Index:     ", s.Index("test", "e"))
    p("Join:      ", s.Join([]string{"a", "b"}, "-"))
    p("Repeat:    ", s.Repeat("a", 5))
    p("Replace:   ", s.Replace("foo", "o", "0", -1))
    p("Replace:   ", s.Replace("foo", "o", "0", 1))
    p("Split:     ", s.Split("a-b-c-d-e", "-"))
    p("ToLower:   ", s.ToLower("TEST"))
    p("ToUpper:   ", s.ToUpper("test"))
}

    
$ go run string-functions.go
Contains:   true
Count:      2
HasPrefix:  true
HasSuffix:  true
Index:      1
Join:       a-b
Repeat:     aaaaa
Replace:    f00
Replace:    f0o
Split:      [a b c d e]
ToLower:    test
ToUpper:    TEST