go语言如何比较字符串

func Equal(s1, s2 string) bool {	return s1 == s2}// 2-使用 compare 比较——区分大小写func Compare(s1, s2 string) bool {	return strings.Compare(s1, s2) == 0 //}//3-EqualFold 比较——不区分大小写. case-fold 即大小写同一处理func EqualFold(s1, s2 string) bool {	return strings.EqualFold(s1, s2)}// 使用等号比较——忽略大小写func Equal2(s1, s2 string) bool {	return strings.ToLower(s1) == strings.ToLower(s2)}// 使用 compare 比较——不区分大小写func Compare2(s1, s2 string) bool {	return strings.Compare(strings.ToLower(s1), strings.ToLower(s2)) == 0}func StringCompareTest() {	fmt.Println("== 区分大小写", Equal("go", "Go")) 	//false	fmt.Println("== 忽略大小写",Equal2("go", "Go"))  //true	fmt.Println("compare 区分大小写",Compare("go", "Go")) //false	fmt.Println("compare 忽略大小写",Compare2("go", "Go")) //true	fmt.Println("EqualFold 忽略大小写",EqualFold("go", "Go")) // true}

package testimport (	"../str"	"testing")func BenchmarkStrEqual(b *testing.B) {	for i := 0; i < b.N; i++ {		str.Equal("go", "Go")	}}func BenchmarkStrEqual2(b *testing.B) {	for i := 0; i < b.N; i++ {		str.Equal2("go", "Go")	}}func BenchmarkStrCompare(b *testing.B) {	for i := 0; i < b.N; i++ {		str.Compare("go", "Go")	}}func BenchmarkStrCompare2(b *testing.B) {	for i := 0; i < b.N; i++ {		str.Compare2("go", "Go")	}}func BenchmarkStrEqualFold(b *testing.B) {	for i := 0; i < b.N; i++ {		str.EqualFold("go", "Go")	}}

package strings// Compare returns an integer comparing two strings lexicographically.// The result will be 0 if a==b, -1 if a < b, and +1 if a > b.//// Compare is included only for symmetry with package bytes.// It is usually clearer and always faster to use the built-in// string comparison operators ==, <, >, and so on.func Compare(a, b string) int {	// NOTE(rsc): This function does NOT call the runtime cmpstring function,	// because we do not want to provide any performance justification for	// using strings.Compare. Basically no one should use strings.Compare.	// As the comment above says, it is here only for symmetry with package bytes.	// If performance is important, the compiler should be changed to recognize	// the pattern so that all code doing three-way comparisons, not just code	// using strings.Compare, can benefit.	if a == b {		return 0	}	if a < b {		return -1	}	return +1}

// EqualFold reports whether s and t, interpreted as UTF-8 strings,// are equal under Unicode case-folding, which is a more general// form of case-insensitivity.func EqualFold(s, t string) bool {	for s != "" && t != "" {		// Extract first rune from each string.		var sr, tr rune		if s[0] < utf8.RuneSelf {			sr, s = rune(s[0]), s[1:]		} else {			r, size := utf8.DecodeRuneInString(s)			sr, s = r, s[size:]		}		if t[0] < utf8.RuneSelf {			tr, t = rune(t[0]), t[1:]		} else {			r, size := utf8.DecodeRuneInString(t)			tr, t = r, t[size:]		}		// If they match, keep going; if not, return false.		// Easy case.		if tr == sr {			continue		}		// Make sr < tr to simplify what follows.		if tr < sr {			tr, sr = sr, tr		}		// Fast check for ASCII.		if tr < utf8.RuneSelf {			// ASCII only, sr/tr must be upper/lower case			if 'A' <= sr && sr <= 'Z' && tr == sr+'a'-'A' {				continue			}			return false		}		// General case. SimpleFold(x) returns the next equivalent rune > x		// or wraps around to smaller values.		r := unicode.SimpleFold(sr)		for r != sr && r < tr {			r = unicode.SimpleFold(r)		}		if r == tr {			continue		}		return false	}	// One string is empty. Are both?	return s == t}