如何判断一字符串是汉字，字母，数字？

Question

要用枚举来比较吗？
求救~！

Answer 1

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }        private void button1_Click(object sender, EventArgs e)
        {
            char a = 'a';
            char b = '8';
            char c = 'L';
          
           
                if (char.IsLetter(a))
                {
                    label1.Text = a + "为字母";
                }
           else
            {
                label1.Text = a + "不为字母";            }            if (char.IsDigit(b))
            {
                label2.Text = b + "为数字";
            }
            else
            {
                label2.Text = b + "不为数字";            }            if (char.IsLetterOrDigit(c))
            {
                label3.Text = c + "为数字或字母";
            }
            else
            {
                label3.Text = c + "不为数字或字母";            }
          
        }
    }
}

Answer 2

Regex.IsMatch("",@"^[\0x4e00-\0x9faf]");
Regex.IsMatch("",@"^[A_Za_z]");
Regex.IsMatch("",@ "^[0-9]+$ "))

Answer 3

static void Main(string[] args)
{
    string[] testArray = new string[] { "全汉字", "All letter", "8888" };
    Regex regExp = new Regex(@"(?isn)^((?<chinese>[\u4E00-\u9FA5]+)|(?<letter>[a-z]+)|(?<num>\d+))$", RegexOptions.Compiled);
    Regex regExp2 = new Regex(@"(?isn)^((?<chinese>[\u4E00-\u9FA5\s]+)|(?<letter>[a-z\s]+)|(?<num>\d+))$", RegexOptions.Compiled);//带标点符号换行支持，看你实际需要选择
    foreach (string test in testArray)
    {
        Match m = regExp2.Match(test);
        Console.Write(test);
        if (m.Groups["chinese"].Success) Console.WriteLine(" 是汉字");
        if (m.Groups["letter"].Success) Console.WriteLine(" 是字母");
        if (m.Groups["num"].Success) Console.WriteLine(" 是数字");
    }
    Console.ReadKey();
}
结果：
全汉字 是汉字
All letter 是字母
8888 是数字