string的本質(zhì)：reflect.StringHeader{}
slice的本質(zhì)：reflect.SliceHeader{}
go指針的本質(zhì)：unsafe.Pointer{}、uintptr{}
獲取slice和string的內(nèi)存地址####
func stringPointer(s string) unsafe.Pointer {
// string的指針本質(zhì)是*reflect.StringHeader
p := (*reflect.StringHeader)(unsafe.Pointer(&s))
return unsafe.Pointer(p.Data)
}
func bytePointer(b []byte) unsafe.Pointer {
// slice的指針本質(zhì)是*reflect.SliceHeader
p := (*reflect.SliceHeader)(unsafe.Pointer(&b))
return unsafe.Pointer(p.Data)
}```
####把[]byte轉(zhuǎn)成string####
類型轉(zhuǎn)換：string(b)债查，為了穩(wěn)定性Go內(nèi)部進(jìn)行了數(shù)據(jù)復(fù)制。
為了獲的更好的性能亲茅，我們可以這樣：
func byteString(b []byte) string {
// reflect.StringHeader和reflect.SliceHeader的結(jié)構(gòu)體相似
return (string)(unsafe.Pointer(&b))
}```
結(jié)構(gòu)體和[]byte互轉(zhuǎn)####
type MyStruct struct {
A int
B int
}
var sizeOfMyStruct = int(unsafe.Sizeof(MyStruct{}))
func MyStructToBytes(s *MyStruct) []byte {
var x reflect.SliceHeader
x.Len = sizeOfMyStruct
x.Cap = sizeOfMyStruct
x.Data = uintptr(unsafe.Pointer(s))
return *(*[]byte)(unsafe.Pointer(&x))
}
func BytesToMyStruct(b []byte) *MyStruct {
return (*MyStruct)(unsafe.Pointer(
(*reflect.SliceHeader)(unsafe.Pointer(&b)).Data,
))
}```
這種方式同樣也適用于string與[]byte互轉(zhuǎn):
var sizeOfString = int(unsafe.Sizeof(""))
func StringtToBytes(s *string) []byte {
var x reflect.SliceHeader
x.Len = sizeOfMyStruct
x.Cap = sizeOfMyStruct
x.Data = uintptr(unsafe.Pointer(s))
return ([]byte)(unsafe.Pointer(&x))
}
func BytesToString(b []byte) string{
return (string)(unsafe.Pointer(
(*reflect.SliceHeader)(unsafe.Pointer(&b)).Data,
))
}```
