Go语言教程之边写边学：基础练习：常用字符串函数（4）

Golang提供了许多内置的字符串函数，它们有助于在处理字符串数据时执行多项操作。Golang字符串函数是核心的一部分。使用此功能无需安装，只需导入"strings"包即可。重要的Golang字符串函数列表如下：

Title函数：

Title函数将每个单词的第一个字符转换为大写。

func Title(s string) string

示例代码：

package main

import (
	"fmt"
	"strings"
)

func main() {
	fmt.Println(strings.Title("Germany is a Western European country with a landscape of forests, rivers, mountain ranges and North Sea beaches."))
	fmt.Println(strings.Title("BAVARIA HESSE BRANDENBURG SAARLAND"))
	fmt.Println(strings.Title("towns and cities"))
}

输出：

Germany Is A Western European Country With A Landscape Of Forests, Rivers, Mountain Ranges And North Sea Beaches.
BAVARIA HESSE BRANDENBURG SAARLAND
Towns And Cities

ToTitle函数：

ToTitle函数将每个单词的所有字符转换为大写。

func ToTitle(s string) string

示例代码：

package main

import (
	"fmt"
	"strings"
)

func main() {
	fmt.Println(strings.ToTitle("Germany is a Western European country with a landscape of forests, rivers, mountain ranges and North Sea beaches."))
	fmt.Println(strings.ToTitle("BAVARIA HESSE BRANDENBURG SAARLAND"))
	fmt.Println(strings.ToTitle("towns and cities"))
}

输出：

GERMANY IS A WESTERN EUROPEAN COUNTRY WITH A LANDSCAPE OF FORESTS, RIVERS, MOUNTAIN RANGES AND NORTH SEA BEACHES.
BAVARIA HESSE BRANDENBURG SAARLAND
TOWNS AND CITIES

ToLower函数：

ToLower函数将每个单词的所有字符转换为小写。

func ToLower(s string) string

示例代码：

package main

import (
	"fmt"
	"strings"
)

func main() {
	fmt.Println(strings.ToLower("Germany is a Western European country with a landscape of forests, rivers, mountain ranges and North Sea beaches."))
	fmt.Println(strings.ToLower("BAVARIA HESSE BRANDENBURG SAARLAND"))
	fmt.Println(strings.ToLower("towns and cities"))
}

输出：

germany is a western european country with a landscape of forests, rivers, mountain ranges and north sea beaches.
bavaria hesse brandenburg saarland
towns and cities

ToUpper函数：

ToUpper函数将每个单词的所有字符转换为大写。

func ToUpper(s string) string

示例代码：

package main

import (
	"fmt"
	"strings"
)

func main() {
	fmt.Println(strings.ToUpper("Germany is a Western European country with a landscape of forests, rivers, mountain ranges and North Sea beaches."))
	fmt.Println(strings.ToUpper("BAVARIA HESSE BRANDENBURG SAARLAND"))
	fmt.Println(strings.ToUpper("towns and cities"))
}

输出：

GERMANY IS A WESTERN EUROPEAN COUNTRY WITH A LANDSCAPE OF FORESTS, RIVERS, MOUNTAIN RANGES AND NORTH SEA BEACHES.
BAVARIA HESSE BRANDENBURG SAARLAND
TOWNS AND CITIES

Trim函数：区分大小写

Trim函数从字符串s的两边删除预定义的字符cutset。

func Trim(s string, cutset string) string

示例代码：

package main

import (
	"fmt"
	"strings"
)

func main() {
	fmt.Println(strings.Trim("0120 2510", "0"))
	fmt.Println(strings.Trim("abcd axyz", "a"))
	fmt.Println(strings.Trim("abcd axyz", "A"))
	fmt.Println(strings.Trim("! Abcd dcbA !", "A"))
	fmt.Println(strings.Trim("! Abcd dcbA !", "!"))
	fmt.Println(strings.Trim(" Abcd dcbA ", " "))
}

输出：

120 251
bcd axyz
abcd axyz
! Abcd dcbA !
 Abcd dcbA
Abcd dcbA

TrimLeft函数：区分大小写

TrimLeft函数仅从字符串s的左侧删除预定义字符剪切集。

func TrimLeft(s string, cutset string) string

示例代码：

package main

import (
	"fmt"
	"strings"
)

func main() {
	fmt.Println(strings.TrimLeft("0120 2510", "0"))
	fmt.Println(strings.TrimLeft("abcd axyz", "a"))
	fmt.Println(strings.TrimLeft("abcd axyz", "A"))
	fmt.Println(strings.TrimLeft("! Abcd dcbA !", "A"))
	fmt.Println(strings.TrimLeft("! Abcd dcbA !", "!"))
	fmt.Println(strings.TrimLeft(" Abcd dcbA ", " "))
}

输出：

120 2510
bcd axyz
abcd axyz
! Abcd dcbA !
 Abcd dcbA !
Abcd dcbA

TrimRight函数：区分大小写

TrimRight函数仅从字符串s的右侧删除预定义的字符剪切集。

func TrimRight(s string, cutset string) string

示例代码：

package main

import (
	"fmt"
	"strings"
)

func main() {
	fmt.Println(strings.TrimRight("0120 2510", "0"))
	fmt.Println(strings.TrimRight("abcd axyz", "a"))
	fmt.Println(strings.TrimRight("abcd axyz", "A"))
	fmt.Println(strings.TrimRight("! Abcd dcbA !", "A"))
	fmt.Println(strings.TrimRight("! Abcd dcbA !", "!"))
	fmt.Println(strings.TrimRight(" Abcd dcbA ", " "))
}

输出：

0120 251
abcd axyz
abcd axyz
! Abcd dcbA !
! Abcd dcbA
 Abcd dcbA

TrimSpace函数：

TrimSpace函数从字符串的两边删除空格和其他预定义字符。
"\t" - 制表符 "\n" - 换行
符 "\x0B" - 垂直制表符 "\r" - 回车符
" " - 普通空格

func TrimSpace(s string) string

示例代码：

package main

import (
	"fmt"
	"strings"
)

func main() {	
	fmt.Println(strings.TrimSpace(" New Zealand is a country in the southwestern Pacific Ocean "))
	fmt.Println(strings.TrimSpace(" \t\n  New Zealand is a country in the southwestern Pacific Ocean \t\n "))
	fmt.Println(strings.TrimSpace(" \t\n\r\x0BNew Zealand is a country in the southwestern Pacific Ocean\t\n "))
}

输出：

New Zealand is a country in the southwestern Pacific Ocean
New Zealand is a country in the southwestern Pacific Ocean
New Zealand is a country in the southwestern Pacific Ocean

TrimPrefix函数：区分大小写

TrimPrefix函数从S字符串的开头删除前缀字符串。如果S不以前缀开头，则返回S不变。

func TrimPrefix(S string, prefix string) string

示例代码：

package main

import (
	"fmt"
	"strings"
)

func main() {
	var s string
	s = "Australia Canada Japan"
	s = strings.TrimPrefix(s, "Australia")
	s = strings.TrimSpace(s)
	fmt.Println(s)
	
	s = "Australia Canada Japan"
	s = strings.TrimPrefix(s, "australia")
	fmt.Println(s)
	
	s = "\nAustralia-Canada-Japan"
	s = strings.TrimPrefix(s, "\n")
	fmt.Println(s)
	
	s = "\tAustralia-Canada-Japan"
	s = strings.TrimPrefix(s, "\t")
	fmt.Println(s)
}

输出：

Canada Japan
Australia Canada Japan
Australia-Canada-Japan
Australia-Canada-Japan