C determines whether the first digit of a string is a number

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Text.RegularExpressions; 
namespace WindowsFormsApplication1
{
public partial class Form1 : Form 
{ 
public Form1() 
{ 
InitializeComponent(); 
} 
private void button1_Click(object sender, EventArgs e) 
{ 
Regex regChina = new Regex( "^[^\x00-\xFF]");
Regex regNum = new Regex( "^[0-9]");
Regex regChar = new Regex( "^[a-z]");
Regex regDChar = new Regex( "^[A-Z]");
string str = "YL 闫磊 ";
if (regNum.IsMatch(str)) 
{ 
MessageBox.Show( " The digital ");
} 
else if (regChina.IsMatch(str)) 
{ 
MessageBox.Show( " Is Chinese ");
} 
else if (regChar.IsMatch(str)) 
{ 
MessageBox.Show( " lowercase ");
} 
else if (regDChar.IsMatch(str)) 
{ 
MessageBox.Show( " A capital ");
} 
} 
} 
}