Case insensitive string search in golang

Question

How do I search through a file for a word in a case insensitive manner?

For example

If I\'m searching for UpdaTe in

Answer 1

If your file is large, you can use regexp and bufio:

//create a regex `(?i)update` will match string contains "update" case insensitive
reg := regexp.MustCompile("(?i)update")
f, err := os.Open("test.txt")
if err != nil {
    log.Fatal(err)
}
defer f.Close()

//Do the match operation
//MatchReader function will scan entire file byte by byte until find the match
//use bufio here avoid load enter file into memory
println(reg.MatchReader(bufio.NewReader(f)))

About bufio

The bufio package implements a buffered reader that may be useful both for its efficiency with many small reads and because of the additional reading methods it provides.