需要用到官方的math包和binary包

package main

import (
	"encoding/binary"
	"fmt"
	"math"
)

func main(){

//float32转[]byte
var sf float32 = 12.12
bits := math.Float32bits(sf)
res:=make([]byte,4)
binary.LittleEndian.PutUint32(res,bits)
fmt.Printf("%v\n",res) //[133 235 65 65]

//[]byte转float32类型
d:=[]byte{133 ,235, 65, 65}
u := binary.LittleEndian.Uint32(d)
frombits := math.Float32frombits(u)
fmt.Println(frombits) //12.12

//float64转[]byte
var f64 =12.324
u64 := math.Float64bits(f64)
res64:=make([]byte,8)
binary.LittleEndian.PutUint64(res64,u64)
fmt.Printf("%v\n",res64) //[217 206 247 83 227 165 40 64]

//[]byte转float64类型
b64:=[]byte{217 ,206 ,247 ,83 ,227 ,165 ,40 ,64}
ui64 := binary.LittleEndian.Uint64(b64)
float64frombits := math.Float64frombits(ui64)
fmt.Println(float64frombits) //12.324

}