Swift 字符串 replacingOccurrences()

import Foundation
var str1 = "bat ball"

// replace b with c
print(str1.replacingOccurrences(of: "b",with: "c"))

// Output: cat call

replacingOccurrences() 语法

replaceOccurrences() 方法的语法是

string.replacingOccurrences(of old: String, with new: String)

此处，string 是 String 类的一个对象。

replacingOccurrences() 参数

replacingOccurences() 方法可以接受两个参数

• old - 你要替换的旧子字符串
• new - 将替换旧子字符串的新子字符串

replacingOccurrences()返回值

• 返回一个字符串的副本，其中 old 子字符串被替换为 new 子字符串

注意：如果找不到 old 子字符串，它将返回原始字符串的副本。

示例 1：Swift 字符串 replacingOccurrences()

import Foundation 

var text = "Java is awesome. Java is fun."

// all occurrences of "Java" is replaced with "Swift"
var new = text.replacingOccurrences(of:"Java", with: "Swift")
print(new)

// "Python" is not the substring of text , so returns original string
var new1 = text.replacingOccurrences(of:"Python", with: "Swift")
print(new1)

输出

Swift is awesome. Swift is fun.
Java is awesome. Java is fun.

在此程序中，text.replacingOccurrences(of:"Python", with: "Swift") 返回原始字符串的副本，因为 "Python" 不是 text 的子字符串。

示例 2：将 replacingOccurrences() 用于字符

import Foundation 

var str1 = "abc cba"

// all occurrences of 'a' is replaced with 'z'
print(str1.replacingOccurrences(of: "a", with: "z"))  // zbc cbz

// all occurences of 'L' is replaced with 'J'
print("Lwift".replacingOccurrences(of: "L", with: "S")) // Swift

// "4" not in the string, so returns original string
print("Hello".replacingOccurrences(of: "4", with:"J"))  // Hello

输出

Swift is awesome. Swift is fun.
Java is awesome. Java is fun.

在此程序中，我们使用了 replacingOccurences() 函数，其中包含：

• str1 - 一个字符串变量
• "Lwift" 和 "Hello" - 字符串字面量