golang各種字串拼接效能對比
摘要：
golang中字串拼接方法
+=
fmt.sprintf
append
buffer.WriteString
copy
廢話不多說，直接上程式碼看效果
package main
import (
"bytes"...
golang中字串拼接方法
- +=
- fmt.sprintf
- append
- buffer.WriteString
- copy
廢話不多說，直接上程式碼看效果
package main
import (
"bytes"
"fmt"
"time"
)
func main() {
str:="chinese"
city:="beijing"
// 1. +=
s:=time.Now()
for i:=0;i<100000;i++ {
str +=city
}
e:=time.Since(s)
fmt.Println("time cost 1:", e)
// 2. fmt.Sprintf
str="chinese"
city="beijing"
s=time.Now()
for i:=0;i<100000;i++ {
str = fmt.Sprintf("%s%s",str,city)
}
e=time.Since(s)
fmt.Println("time cost 2:", e)
//3.buffer.WriteString
str="chinese"
city="beijing"
s=time.Now()
var buf= bytes.Buffer{}
buf.WriteString(str)
for i:=0;i<100000;i++ {
buf.WriteString(city)
}
e=time.Since(s)
fmt.Println("time cost 3:", e)
//4. append
str="chinese"
city="beijing"
s=time.Now()
bstr:=[]byte(str)
bcity:=[]byte(city)
for i:=0;i<100000;i++ {
bstr= append(bstr, bcity...)
}
e=time.Since(s)
fmt.Println("time cost 4:", e)
// 5. copy
str="chinese"
city="beijing"
s=time.Now()
zstr :=[]byte(str)
for i:=0;i<100000;i++ {
copy(zstr, city)
}
e=time.Since(s)
fmt.Println("time cost 5:", e)
}
最終效果（多次嘗試，對比結果都一致）：
time cost 1: 3.176250251s time cost 2: 5.347827717s time cost 3: 1.051104ms time cost 4: 769.258µs time cost 5: 323.968µs
效率：copy > append > buf.WriteString > += > fmt.Sprintf
所以請慎用fmt.Sprinf 和 +=