How do I compare strings in GoLang?

go
user2202911 picture user2202911 · Dec 20, 2015 · Viewed 122.8k times · Source

I am unable to produce a 'true' result when it comes to Go string comparison. I wrote the following to explain the issue and attached a screenshot of the output

// string comparison in Go
package main
import "fmt"
import "bufio"
import "os"

func main() {
    var isLetterA bool 

    fmt.Println("Enter the letter a")
    reader := bufio.NewReader(os.Stdin)
    input, _ := reader.ReadString('\n')

    if(input == "a") {
        isLetterA = true
    } else {
        isLetterA = false 
    }

    fmt.Println("You entered",input)
    fmt.Println("Is it the letter a?",isLetterA)

}

example

Answer

helmbert picture helmbert · Dec 20, 2015

== is the correct operator to compare strings in Go. However, the strings that you read from STDIN with reader.ReadString do not contain "a", but "a\n" (if you look closely, you'll see the extra line break in your example output).

You can use the strings.TrimRight function to remove trailing whitespaces from your input:

if strings.TrimRight(input, "\n") == "a" {
    // ...
}

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