Golang 统计字符串中数字字母数量的实现方法

// GetAlphanumericNumByASCII 根据 ASCII 码值获取字母数字数量。
func GetAlphanumericNumByASCII(s string) int {
	num := int(0)
	for i := 0; i < len(s); i++ {
		switch {
		case 48 <= s[i] && s[i] <= 57: // 数字
			fallthrough
		case 65 <= s[i] && s[i] <= 90: // 大写字母
			fallthrough
		case 97 <= s[i] && s[i] <= 122: // 小写字母
			num++
		default:
		}
	}
	return num
}

// 或者
// GetAlphanumericNumByASCIIV2 根据 ASCII 码值获取字母数字数量。
func GetAlphanumericNumByASCIIV2(s string) int {
	num := int(0)
	for _, c := range s {
		switch {
		case '0' <= c && c <= '9':
			fallthrough
		case 'a' <= c && c <= 'z':
			fallthrough
		case 'A' <= c && c <= 'Z':
			num++
		default:
		}
	}
	return num
}

// GetAlphanumericNumByRegExp 根据正则表达式获取字母数字数量。
func GetAlphanumericNumByRegExp(s string) int {
	rNum := regexp.MustCompile(`\d`)
	rLetter := regexp.MustCompile("[a-zA-Z]")
	return len(rNum.FindAllString(s, -1)) + len(rLetter.FindAllString(s, -1))
}

package string
import "testing"
func TestGetAlphanumericNumByASCII(t *testing.T) {
	type args struct {
		s string
	}
	tests := []struct {
		name string
		args args
		want int
	}{
		{
			name: "包含数字",
			args: args{"108条梁山好汉"},
			want: 3,
		},
		{
			name: "包含字母",
			args: args{"一百条梁山man"},
			want: 3,
		},
		{
			name: "包含数字与字母",
			args: args{"108条梁山man"},
			want: 6,
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if got := GetAlphanumericNumByASCII(tt.args.s); got != tt.want {
				t.Errorf("GetAlphanumericNumByASCII() = %v, want %v", got, tt.want)
			}
		})
	}
}
func TestGetAlphanumericNumByASCIIV2(t *testing.T) {
	type args struct {
		s string
	}
	tests := []struct {
		name string
		args args
		want int
	}{
		{
			name: "包含数字",
			args: args{"108条梁山好汉"},
			want: 3,
		},
		{
			name: "包含字母",
			args: args{"一百条梁山man"},
			want: 3,
		},
		{
			name: "包含数字与字母",
			args: args{"108条梁山man"},
			want: 6,
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if got := GetAlphanumericNumByASCIIV2(tt.args.s); got != tt.want {
				t.Errorf("GetAlphanumericNumByASCII() = %v, want %v", got, tt.want)
			}
		})
	}
}
func TestGetAlphanumericNumByRegExp(t *testing.T) {
	type args struct {
		s string
	}
	tests := []struct {
		name string
		args args
		want int
	}{
		{
			name: "包含数字",
			args: args{"108条梁山好汉"},
			want: 3,
		},
		{
			name: "包含字母",
			args: args{"一百条梁山man"},
			want: 3,
		},
		{
			name: "包含数字与字母",
			args: args{"108条梁山man"},
			want: 6,
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if got := GetAlphanumericNumByRegExp(tt.args.s); got != tt.want {
				t.Errorf("GetAlphanumericNumByRegExp() = %v, want %v", got, tt.want)
			}
		})
	}
}

func BenchmarkGetAlphanumericNumByASCII(b *testing.B) {
	for n := 0; n < b.N; n++ {
		GetAlphanumericNumByASCII("108条梁山man")
	}
}
func BenchmarkGetAlphanumericNumByASCIIV2(b *testing.B) {
	for n := 0; n < b.N; n++ {
		GetAlphanumericNumByASCIIV2("108条梁山man")
	}
}
func BenchmarkGetAlphanumericNumByRegExp(b *testing.B) {
	for n := 0; n < b.N; n++ {
		GetAlphanumericNumByRegExp("108条梁山man")
	}
}

package main
import (
	"fmt"
	huge "GitHub.com/dablelv/go-huge-util"
)
func main() {
	fmt.Println(huge.GetAlphanumericNumByASCII("108条梁山man"))  	// 6
	fmt.Println(huge.GetAlphanumericNumByASCIIV2("108条梁山man"))  	// 6
	fmt.Println(huge.GetAlphanumericNumByRegExp("108条梁山man")) 	// 6
}