golang 字符串拼接性能的对比分析

// fmt.Printf
func BenchmarkFmtSprintfMore(b *testing.B) {
 var s string
 for i := 0; i < b.N; i++ {
  s += fmt.Sprintf("%s%s", "hello", "world")
 }
 fmt.Errorf(s)
}
// 加号 拼接
func BenchmarkAddMore(b *testing.B) {
 var s string
 for i := 0; i < b.N; i++ {
  s += "hello" + "world"
 }
 fmt.Errorf(s)
}

// strings.Join
func BenchmarkStringsJoinMore(b *testing.B) {

 var s string
 for i := 0; i < b.N; i++ {
  s += strings.Join([]string{"hello", "world"}, "")

 }
 fmt.Errorf(s)
}

// bytes.Buffer
func BenchmarkBufferMore(b *testing.B) {

 buffer := bytes.Buffer{}
 for i := 0; i < b.N; i++ {
  buffer.WriteString("hello")
  buffer.WriteString("world")

 }
 fmt.Errorf(buffer.String())
}

~/gopath/src/test/string  go test -bench="."
goos: darwin
goarch: amd64
pkg: test/string
BenchmarkFmtSprintfMore-4   300000  118493 ns/op
BenchmarkAddMore-4    300000  124940 ns/op
BenchmarkStringsJoinMore-4  300000  117050 ns/op
BenchmarkBufferMore-4   100000000   37.2 ns/op
PASS
ok  test/string 112.294s

func BenchmarkFmtSprintf(b *testing.B) {
 for i := 0; i < b.N; i++ {
  s := fmt.Sprintf("%s%s", "hello", "world")
  fmt.Errorf(s)
 }

}

func BenchmarkAdd(b *testing.B) {
 for i := 0; i < b.N; i++ {
  s := "hello" + "world"
  fmt.Errorf(s)
 }
}
func BenchmarkStringsJoin(b *testing.B) {
 for i := 0; i < b.N; i++ {
  s := strings.Join([]string{"hello", "world"}, "")
  fmt.Errorf(s)
 }
}
func BenchmarkBuffer(b *testing.B) {

 for i := 0; i < b.N; i++ {
  b := bytes.Buffer{}
  b.WriteString("hello")
  b.WriteString("world")
  fmt.Errorf(b.String())
 }
}

 ~/gopath/src/test/string  go test -bench="."
goos: darwin
goarch: amd64
pkg: test/string
BenchmarkFmtSprintf-4  10000000   200 ns/op
BenchmarkAdd-4    20000000   93.6 ns/op
BenchmarkStringsJoin-4  10000000   152 ns/op
BenchmarkBuffer-4   10000000   175 ns/op
PASS
ok  test/string 7.818s

import (
 "github.com/typa01/go-utils"
)

func TestStringBuilderReplace(t *testing.T) {
 builder1 := NewStringBuilder()
 builder1.Append("%111%abc%987%")
 FmtPrintln(builder1.Replace("%", "$").ToString()) // $111$abc$987$
 builder2 := builder1.Clear()
 builder2.AppendStrings("abc","defg").AppendInt(123).AppendFloat64(66.44).AppendStrings("aaa", "bbb", "&")
 FmtPrintln(builder2.RemoveLast().ToString()) // abcdefg1236.644E+01aaabbb
 str1 := NewString("123")
 builder3 := NewStringBuilderString(str1).Append("456")
 FmtPrintln(builder3.ToString()) // 123456
}