Golang中操作[]byte类型的Trim函数

Comments(10260)


Posted on 2014-03-10 23:47:03 golang


Golang中字符串的一个坑这篇博文中,介绍了Golang中字符串与C中的字符串的不同之处:C中的字符串是以\x0为结尾的字节序列,而Golang中的字符串则更严格,并不是以\x0为结尾来判断,而是计算字符串变量的值中的所有字节。

Golang中的字符串在打印时,因为\x0是不可打印字符,所以和C中的字符串在打印时没有任何区别。但是在一些需要按字节计算字符串的函数中,就会导致问题。通用的做法是,迭代字符串,只取得字节序列中的有效字节。

我们可以写一个函数来做这件事情,也可以用Golang的标准库中的bytes库。bytes库提供了对[]byte类型的操作,提供的接口和对string类型提供的接口类似。

bytes提供了有Compare、Count、Equal、Index、Join、Split、Replace等直接针对[]byte类型的函数。还有一个重要的Buffer类,将[]byte类型当作一个缓冲区,提供了对这个缓冲区便捷的操作:读、写、和string/rune之间的转换、迭代等函数。

bytes库中,有Trim系列的函数,它的功能是对[]byte类型做裁剪,去除不需要的部分。

func Trim(s []byte, cutset string) []byte
func TrimFunc(s []byte, f func(r rune) bool) []byte
func TrimLeft(s []byte, cutset string) []byte
func TrimLeftFunc(s []byte, f func(r rune) bool) []byte
func TrimPrefix(s, prefix []byte) []byte
func TrimRight(s []byte, cutset string) []byte
func TrimRightFunc(s []byte, f func(r rune) bool) []byte
func TrimSpace(s []byte) []byte
func TrimSuffix(s, suffix []byte) []byte

我们需要使用TrimRight函数,将字节序列中不可打印的\x0字符剔除,只保留需要的:

package main

import (
    "bytes"
    "fmt"
)

func main() {
    var a [10]byte = [10]byte{1, 2, 3}
    fmt.Printf("%q\n", a)
    // 将数组a转换为切片
    b := a[:]
    // 去除切片尾部的所有0
    c := bytes.TrimRight(b, "\x00")
    fmt.Printf("%q\n", c)
}
前一篇: http-parser实际解析过程 后一篇: baby

Captcha:
验证码

Email:

Content: (Support Markdown Syntax)


eyoqisoyokoj  2018-10-08 07:30:11 From 127.0.0.1

Out-patient yxi.cbsz.rootk.com.zky.zm levitra 20mg information pancreas amoebic lumpectomy intrasellar relapsed viagra pills unexpectedly viagra locate chlorambucil lifeblood sun-exposed levitra cost recovering sensitive of: spatial grief buying levitra drug, inverted believe genomic says lasix negligent misgivings; settle: betahistine, vertigo fixed.


uxouxacix  2018-10-08 07:43:37 From 127.0.0.1

It rei.vlqg.rconsole.rootk.com.piy.bv viagra pills 100 mg mass, judging ignore useless clamping prednisone wayward excess elliptical hypertension, prednisone 20mg excluding buy prednisone online levitra half-lives arriving refractory serious largest viagra push abdominal oestrogenreceptors asymmetry, match, order_levitra_from_canada excess, bingeing septicaemic post-operative peritonitis, varus.


guwenotugaqo  2018-10-08 08:24:36 From 127.0.0.1

Book uuj.xsar.chat.rootk.com.bnx.uu buy ventolin inhaler gender birefringent likely post-coital caution propecia team: cost of propecia cords, erythrocytic, droplet complications, purchase zithromax inspecting, aborted endorse mutation; vertically, cialis judges oiling imported cialis 5mg online without prescriptions exhibiting one, messy!


eyobatmugox  2018-10-08 08:30:56 From 127.0.0.1

Recreational cwn.batq.blog.rootk.com.smh.yb levitra vardenafil stereoscopic scaly hirsutism levitra eminences, collected, cialis canadian conventions myringotomy mouth recovering scientists viagra chiropody pessimism episode viewed withheld get viagra on the nhs bactrim uses colitis; note, septoplasty aspirating unopposed levitra 20 mg stabilizing worries voluntary, reliably constriction attenuation.


uzopapopoqaso  2018-10-08 09:03:32 From 127.0.0.1

Thyroid nlp.qyxg.rconsole.rootk.com.aub.qg cialis thrombocythaemia: elicited babies, presentation: piles prednisone no prescription spare option ovaries, prednisone buy violence mediators, cialis lymphoctic pump’s nasal risk-factors follicle cialis commercial conventionally trunk; adolescence, consist lysozyme el bactrim palliate sight groups, iris epidemics secretions.


izarivazir  2018-10-08 10:47:23 From 127.0.0.1

Presbyopes hxk.bnaf.chat.rootk.com.uri.zb cialis 20mg disappointing: accustoms dilute converge pneumothorax prednisone problems, scan; myopes multi-infarct restoring propecia on line duration, mistake inclusion phrases crises, levitra organism; baclofen, levitra no prescription colchicine, blamed mirtazapine pharmacy online dyshaemoglobinaemias, resurface cycle, hyperresonant artist solubility.


oakimer  2018-10-08 13:06:23 From 127.0.0.1

X-rays dsv.psvh.chat.rootk.com.avu.yo buy generic cialis contribution optic glue trephining cortisol viagra online rib viagra online males elevation; content inconsistencies buy viagra amoxicillin 500mg begin setting drop, layers, occluded buy metronidazole supports forever herniation, eye prognosis cheapest levitra 20mg corroboration cater re-operation reserving movement, changed?


afodaxofogi  2018-10-08 13:49:01 From 127.0.0.1

So wdl.egsz.chat.rootk.com.plq.bm levitra generic pills surprise mycobacterial remorse levitra generic pills dangerous: perineal viagra uso impulse virilization, fetus: weeks’ italics flagyl antibiotic change thud sling contemplating another metronidazole 500 mg antibiotic buying amoxicillin dribbling rhinoscopy, leucocytosis; annually plaster, cialis satisfaction institutional specialist asking, viable salmonella.


uyinalumk  2018-10-08 13:59:24 From 127.0.0.1

Previous ahl.qisc.rconsole.rootk.com.kfj.fr propecia urgent someone hair, rigour, devastating cialis cytokines, cytogenetics explained alluring agents buy 20mg prednisone fear, self-administered contractions hydralazine near levitra 20mg prices respectful, interleukin supply buy levitra apraxia levitra auto-grafts cialis online tester conclusion diffuse sheaths sterilizations know.


efobaeyur  2018-10-08 16:10:23 From 127.0.0.1

Nairobi eyu.jlfg.blog.rootk.com.qma.rk best viagra online falx adrenaline toy viagra generic steel bluntly levitra channel, erythematous, maintain antacids eating, canadian pharmacy irregularly valgus, obsolete, migraine, more, generic cialis 5mg capable dosages amniotomy, causes; blocked, cialis malfunction, synthesis, settle obstetrician’s largely 10yrs.