Go字符串拼接常见的方式有加号、fmt.Sprintf、strings.Builder、bytes.Buffer、strings.join、切片。

package concat_stringimport ("bytes""fmt""strconv""strings""testing"
)const numbers = 100// +
func BenchmarkStringAdd(b *testing.B) {b.ResetTimer()for idx := 0; idx < b.N; idx++ {var s stringfor i := 0; i < numbers; i++ {s += strconv.Itoa(i)}}b.StopTimer()
}// fmt.Sprintf
func BenchmarkSprintf(b *testing.B) {b.ResetTimer()for idx := 0; idx < b.N; idx++ {var s stringfor i := 0; i < numbers; i++ {s = fmt.Sprintf("%v%v", s, i)}}b.StopTimer()
}// strings.Builder
func BenchmarkStringBuilder(b *testing.B) {b.ResetTimer()for idx := 0; idx < b.N; idx++ {var builder strings.Builderfor i := 0; i < numbers; i++ {builder.WriteString(strconv.Itoa(i))}_ = builder.String()}b.StopTimer()
}// bytes.Buffer
func BenchmarkBytesBuf(b *testing.B) {b.ResetTimer()for idx := 0; idx < b.N; idx++ {var buf bytes.Bufferfor i := 0; i < numbers; i++ {buf.WriteString(strconv.Itoa(i))}_ = buf.String()}b.StopTimer()
}// strings.join
func BenchmarkStringsJoin(b *testing.B) {b.ResetTimer()var strs []stringfor i := 0; i < b.N; i++ {strs = append(strs, strconv.Itoa(i))}_ = strings.Join(strs, "")b.StopTimer()
}// 切片
func BenchmarkByteSliceString(b *testing.B) {b.ResetTimer()buf := make([]byte, 0)for i := 0; i < b.N; i++ {buf = append(buf, byte(i))}_ = string(buf)b.StopTimer()
}

go test -bench=.

244851 4725 ns/op 表示单位时间内（默认是1s）被测函数运行了 244851次，每次运行耗时 4725ns
总耗时10.261s。
https://www.cnblogs.com/cheyunhua/p/15769717.html
http://t.zoukankan.com/yahuian-p-go-benchmark.html