一、ASCII 介绍
英语的字母大小写转化，是咱们常遇到的字符串解决状况。
一、go 中解决字符串 转化小写
func ToLower(s string) string {b := strings.Builder{}
b.Grow(len(s))
for i := 0; i < len(s); i++ {c := s[i]
if 'A' <= c && c <= 'Z' {c += 'a' - 'A'}
b.WriteByte(c)
}
return b.String()}测试函数：
import "testing"
func TestToLower(t *testing.T) {
type args struct {s string}
tests := []struct {
name string
args args
want string
}{{"1", args{s: "A"}, "a"},
{"1", args{s: "Aa"}, "aa"},
{"1", args{s: "Aa0"}, "aa0"},
{"1", args{s: ")A_$"}, ")a_$"},
{"1", args{s: "0000"}, "0000"},
{"1", args{s: "哈哈 a"}, "哈哈 a"},
{"1", args{s: "哈哈 A 啊啊"}, "哈哈 a 啊啊"},
}
for _, tt := range tests {t.Run(tt.name, func(t *testing.T) {if got := ToLower(tt.args.s); got != tt.want {t.Errorf("ToLower() = %v, want %v", got, tt.want)
}
})
}
}