File Extension in GO
Captures the file extension from a filename.
Try it in the GO tester →Pattern
regexGO
\.([A-Za-z0-9]+)$Go (RE2) code
goGo
package main
import (
"fmt"
"regexp"
)
func main() {
re := regexp.MustCompile(`\.([A-Za-z0-9]+)$`)
input := `document.pdf`
for _, match := range re.FindAllString(input, -1) {
fmt.Println(match)
}
}Uses `regexp.MustCompile` (panics on bad patterns at startup) and `FindAllString` for all matches.
How the pattern works
`\.` matches the literal dot. `([A-Za-z0-9]+)$` captures alphanumeric characters up to the end of the string.
Examples
Input
document.pdfMatches
.pdf
Input
archive.tar.gzMatches
.gz
Input
no-extensionNo match
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