1. 定义字符串类型

package main

import ("fmt");

func main() {

    var str1 string = "你好 GoLang 1"
    var str2 = "你好 GoLang 2"
    str3 := "你好 GoLang 3"

    fmt.Printf("%v--%T\n", str1, str1)
    // 你好 GoLang 1--string
    fmt.Printf("%v--%T\n", str2, str2)
    // 你好 GoLang 2--string
    fmt.Printf("%v--%T\n", str3, str3)
    // 你好 GoLang 1--string
}

2. 字符串转义符

package main

import ("fmt");

func main() {

    str1 := "this \n is string" 
    fmt.Println(str1)
    // this 
    //   is string

    str2 := "C:\\Go\\bin"
    fmt.Println(str2)
    // C:\Go\bin

}

3. 多行字符串

package main
import ("fmt");
func main() {
    str := `this is a
        this is b
        this is c
        this is d
        this is e
    `
    fmt.Println(str)

    // this is a        
    //     this is b
    //     this is c
    //     this is d
    //     this is e
}

4. 求字符串长度

package main

import ("fmt");

func main() {
    var str1 = "aaaa"
    fmt.Println(len(str1))
    // 4

    var str2 = "你好" 
    fmt.Println(len(str2))
    // 6
}

5. 拼接字符串

package main

import ("fmt");

func main() {

    str1 := "你好"
    str2 := "Golang"
    str3 := str1 + str2
    fmt.Println(str3)
    // 你好Golang

    str4 := "你好"
    str5 := "世界"
    str6 := fmt.Sprintf("%v %v", str4, str5)
    fmt.Println(str6)
    // 你好 世界


    str7 := "反引号间换行将被作为字符串中的换行," +
    	"文本将会原样输出," +
    	"但是所有的转义字符均无效"
    fmt.Println(str7)
    // 反引号间换行将被作为字符串中的换行,文本将会原样输出,但是所有的转义字符均无效

}

6. 字符串分割

package main
import ("fmt";"strings")
func main() {
    var str = "123-456-789"
    arr := strings.Split(str, "-")
    fmt.Println(arr)
    // [123 456 789] // 返回一个切片
}

7. 切片链接成字符串

package main

import ("fmt";"strings");

func main() {

    var str1 = "123-456-789"
    arr1 := strings.Split(str1, "-")
    str2 := strings.Join(arr1, "*")
    fmt.Println(str2) 
    // 123*456*789

    arr2 := []string{"php", "java", "golang"} 
    str3 := strings.Join(arr2, "-")
    fmt.Printf("%v - %T", str3, str3)
    // php-java-golang - string

}

8. 判断是否包含

package main

import ("fmt";"strings");

func main() {

    str1 := "this is str"

    str2 := "this"
    flag1 := strings.Contains(str1, str2)
    fmt.Println(flag1)
    // true 

    str3 := "thisxxx"
    flag2:= strings.Contains(str1, str3)
    fmt.Println(flag2)
    // false
    
}

9. 前缀/后缀判断

package main

import ("fmt";"strings");

func main() {

    str := "this is str"

    str1 := "this"
    flag1 := strings.HasPrefix(str, str1)
    fmt.Println(flag1)
    // true

    str2 := "str"
    flag2 := strings.HasSuffix(str, str2)
    fmt.Println(flag2)
    // true

}

10. 从前查找字符串位置

package main

import ("strings");

func main() {

    str := "this is str"

    str1 := "is"
    num1 := strings.Index(str, str1)
    println(num1) 
    // 2

    str2 := "xxx"
    num2 := strings.Index(str, str2)
    println(num2) 
    // -1 

}

11. 从后查找字符串位置

package main

import ("strings");

func main() {
    str1 := "this is str"
    str2 := "is"
    num := strings.LastIndex(str1, str2)
    println(num)  
    // 5
}