SHA1散列经常用于计算二进制或文本块的短标识。 例如，git版本控制系统广泛使用SHA1s来标识版本化的文件和目录。下面是如何在Go中计算SHA1哈希值。
Go在各种crypto/*包中实现了几个哈希函数。
所有的示例代码，都放在
F:\worksp\golang目录下。安装Go编程环境请参考：http://www.yiibai.com/go/go_environment.html
sha1-hashes.go的完整代码如下所示 -
package main
// Go implements several hash functions in various
// `crypto/*` packages.
import "crypto/sha1"
import "fmt"
func main() {
s := "sha1 this string"
// The pattern for generating a hash is `sha1.New()`,
// `sha1.Write(bytes)`, then `sha1.Sum([]byte{})`.
// Here we start with a new hash.
h := sha1.New()
// `Write` expects bytes. If you have a string `s`,
// use `[]byte(s)` to coerce it to bytes.
h.Write([]byte(s))
// This gets the finalized hash result as a byte
// slice. The argument to `Sum` can be used to append
// to an existing byte slice: it usually isn't needed.
bs := h.Sum(nil)
// SHA1 values are often printed in hex, for example
// in git commits. Use the `%x` format verb to convert
// a hash results to a hex string.
fmt.Println(s)
fmt.Printf("%x\n", bs)
}
执行上面代码，将得到以下输出结果 -
F:\worksp\golang>go run sha1-hashes.go
sha1 this string
cf23df2207d99a74fbe169e3eba035e633b65d94
