如何在golang中交换字符串的子字符串？

问题描述

我正在尝试学习Go-lang，因此在Go中玩弦乐。但是我无法在字符串中执行正确的子字符串交换。

我的代码是：

package main

import (
    "fmt"
    "strings"
)

func main() {
    mystr := "I have an apple but not a mango,and she has a mango but not an apple"
    fmt.Println(mystr)
    mystr = strings.ReplaceAll(mystr,"apple","(apple)")
    mystr = strings.ReplaceAll(mystr,"mango","apple")
    mystr = strings.ReplaceAll(mystr,"(apple)","mango")
    fmt.Println(mystr)
    mystr = strings.ReplaceAll(mystr,"an","(a)")
    mystr = strings.ReplaceAll(mystr,"a","an")
    mystr = strings.ReplaceAll(mystr,"(an)","a")
    fmt.Println(mystr)
}

输出：

I have an apple but not a mango,and she has a mango but not an apple
I have an mango but not a apple,and she has a apple but not an mango
I hanve a mago but not an anpple,ad she hans an anpple but not a mago

是否有一种输入列表或字典的方式（例如在python中），所以我可以定义交换位置，而无需多次使用 strings.ReplaceAll（）。

例如：

苹果->芒果

芒果->苹果

a-> an

an-> a

所需的输出：

 I have a mango but not an apple,and she has an apple but not a mango

如果有多种方法，我将很高兴了解每种方法的优缺点。

解决方法

strings.ReplaceAll()不执行“切换”，只是将 some 字符串的出现替换为另一个；但不会执行将另一个替换为 some 。意味着ReplaceAll(s,"a","b")将所有出现的"a"替换为"b"，但不会替换"b"的出现"a"。

这是2个替换操作。并且这2个替换操作无法顺序执行，因为一旦将“ apple”替换为“ mango”，您将只有“ mango”，因此如果要用“ apple”替换“ mango” s，只剩下“苹果”。

相反，您可以使用strings.Replacer在其中列出多个可替换对，并且其Replacer.Replace()方法将一步执行所有替换。

还请注意，您不应将所有“ a”替换为“ an”，因为输入中可能会存在其他“ a”，而不仅仅是“ mango”之前。最好是用“芒果”代替“苹果”，反之亦然。

s := "I have an apple but not a mango,and she has a mango but not an apple"
fmt.Println(s)

r := strings.NewReplacer("an apple","a mango","an apple")
s = r.Replace(s)
fmt.Println(s)

输出（在Go Playground上尝试）：

I have an apple but not a mango,and she has a mango but not an apple
I have a mango but not an apple,and she has an apple but not a mango

go string string swap