C#生成中文汉字验证码源码

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Drawing;
using System.Text;

public partial class Admin_ValidCode : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
this.CreateCheckCodeImage(GenerateCheckCode());

}
private string GenerateCheckCode()
{
int number;
//char code;
string checkCode = String.Empty;

System.Random random = new Random();

Encoding gb = Encoding.GetEncoding("gb2312");
//调用函数产生4个随机中文汉字编码
object[] bytes = CreateRegionCode(6);
//根据汉字编码的字节数组解码出中文汉字
string str1 = gb.GetString((byte[])Convert.ChangeType(bytes[0], typeof(byte[])));
string str2 = gb.GetString((byte[])Convert.ChangeType(bytes[1], typeof(byte[])));
string str3 = gb.GetString((byte[])Convert.ChangeType(bytes[2], typeof(byte[])));
string str4 = gb.GetString((byte[])Convert.ChangeType(bytes[3], typeof(byte[])));
//输出的控制台
checkCode = str1 + str2 + str3 + str4;

//for (int i = 0; i < 5; i++)
//{
// number = random.Next();

// if (number % 2 == 0)
// code = (char)('0' + (char)(number % 10));
// else
// code = (char)('A' + (char)(number % 26));

// checkCode += code.ToString();
/