strings.HasPrefix(s string,preffix string) bool:

stirngs.HasSuffix(s string,suffix string) bool:

strings.Index(s string,str string) int:

strings.LastIndex(s string,str string) int:strings.LastIndex(s string,s

strings.Replace(str string,old string,new string,n int):

strings.Count(str string,count int)string:

strings.Repeat(str string,count int) string:

strings.ToLower(str string)

strings.ToUpper(str string)string:

strings.TrimSpace(str string):

strings.Trim(str string,cut string):

strings.TrimLeft(str string,cut string):

strings.TrimRight(str string,cunt string):

strings.Field(str string):

string.Split(str string,split string):

strings.Join(s1 []string,sep string):　　

package strTest

import (
    "fmt"
    "strings"
    "strconv"
)

func StrUse(name string) string {
    result := strings.HasPrefix(name,"y")  //HasSuffix 以什么结尾

    firstStr :=strings.Index(name,"z")    // 首字符以什么开头
    lastStr :=strings.LastIndex(name,"z")
    fmt.Println(firstStr,lastStr)

    strNum :=strings.Count("zzy","z")  //计数
    fmt.Printf("z的数量%d\n",strNum)

    lowerStr := strings.ToLower("Zzy")   //大写ToUpper
    fmt.Println(lowerStr)

    stripSpace := strings.TrimSpace(" zzy ")  //去守卫空格，TrimLeft 去掉字符串首部cut字符  TrimRight 去掉字符串尾部cut字符
    fmt.Println(stripSpace)

    strSlice := strings.Split("zczrtzs","z")  // 返回str split分割的所有子串的slice
    fmt.Println(strSlice)

    strJoin := strings.Join(strSlice,"*")  //用*把Split分割中的所有元素连接起来
    fmt.Println("join:", strJoin)
    
    //strconv 把一个整数转换成字符串 strconv.Itoa(c)
    intToStr :=strconv.Itoa(1)   //一个字符串转换成整数 stronv.Atio(str string)(int,errror):
    fmt.Println(intToStr)

    if !result{
        message := fmt.Sprintf("%v不是y开头",name)
        return message
    }
    message :=fmt.Sprintf("%v是y开头",name)
    return message
        
}