png.aspx.cs

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.Drawing2D;
using System.Drawing.Imaging;
using System.Drawing.Text;
using System.Drawing;
using System.Text;
//5_1_a_s_p_x.c_o_m

public partial class png : System.Web.UI.Page
{
private readonly string ImagePath = "Validator.jpg";
private static string gif = "";

protected void Page_Load(object sender, EventArgs e)
{

switch (Request.QueryString["aa"])
{
case "1":
gif = stxt();
Session["gif"]= stxt();
break;
case "2":
gif = GetRandomint();
Session["gif"]= GetRandomint();
break;
case "3":
gif = RndNum(3);
Session["gif"]= RndNum(3);
break;
default:
gif = RndNum(3);
Session["gif"]= GetRandomint();
break;
}

///创建Bmp位图
Bitmap bitMapImage = new System.Drawing.Bitmap(Server.MapPath(ImagePath));
Graphics graphicImage = Graphics.FromImage(bitMapImage);

///设置画笔的输出模式
graphicImage.SmoothingMode = SmoothingMode.HighSpeed;
///添加文本字符串
graphicImage.DrawString(gif, new Font("Arial", 20, FontStyle.Bold), SystemBrushes.WindowText, new Point(0, 0));

///设置图像输出的格式
Response.ContentType = "image/jpeg";

///保存数据流
bitMapImage.Save(Response.OutputStream, ImageFormat.Jpeg);

///释放占用的资源
graphicImage.Dispose();
bitMapImage.Dispose();
}
private String GetRandomint()
{
Random random = new Random();
return (random.Next(100000, 999999).ToString());
}
/**//*
此函数在汉字编码范围内随机创建含两个元素的十六进制字节数组，每个字节数组代表一个汉字，并将
四个字节数组存储在object数组中。
参数：strlength，代表需要产生的汉字个数
*/
public static object[] CreateRegionCode(int strlength)
{
//定义一个字符串数组储存汉字编码的组成元素
string[] rBase=new String [16]{"0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"};

Random rnd=new Random();

//定义一个object数组用来
object[] bytes=new object[strlength];

/**//*每循环一次产生一个含两个元素的十六进制字节数组，并将其放入bject数组中
每个汉字有四个区位码组成
区位码第1位和区位码第2位作为字节数组第一个元素
区位码第3位和区位码第4位作为字节数组第二个元素
*/
for(int i=0;i {
//区位码第1位
int r1=rnd.Next(11,14);
string str_r1=rBase[r1].Trim();

//区位码第2位
rnd=new Random(r1*unchecked((int)DateTime.Now.Ticks)+i);//更换随机数发生器的种子避免产生重复值
int r2;
if (r1==13)
{
r2=rnd.Next(0,7);
}
else
{
r2=rnd.Next(0,16);
}
string str_r2=rBase[r2].Trim();

//区位码第3位
rnd=new Random(r2*unchecked((int)DateTime.Now.Ticks)+i);
int r3=rnd.Next(10,16);
string str_r3=rBase[r3].Trim();

//区位码第4位
rnd=new Random(r3*unchecked((int)DateTime.Now.Ticks)+i);
int r4;
if (r3==10)
{
r4=rnd.Next(1,16);
}
else if (r3==15)
{
r4=rnd.Next(0,15);
}
else
{
r4=rnd.Next(0,16);
}
string str_r4=rBase[r4].Trim();

//定义两个字节变量存储产生的随机汉字区位码
byte byte1=Convert.ToByte(str_r1 + str_r2,16);
byte byte2=Convert.ToByte(str_r3 + str_r4,16);
//将两个字节变量存储在字节数组中
byte[] str_r=new byte[]{byte1,byte2};

//将产生的一个汉字的字节数组放入object数组中
bytes.SetValue(str_r,i);

}

return bytes;

}
private string stxt()
{
Encoding gb = Encoding.GetEncoding("gb2312");

//调用函数产生4个随机中文汉字编码
object[] bytes = CreateRegionCode(3);

//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 txt = str1 + str2 + str3;
return txt;
}
///

/// 这个是使用文字,字母,数字混合
///

///
///
public String RndNum(int VcodeNum)
{
String Vchar = "0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,W,X,Y,Z,呵,哈,弹,簧,秤,嬉,戏";
String[] VcArray = Vchar.Split(',');
String VNum = "";
Random random = new Random();
for (int i = 1; i <= VcodeNum; i++)
{
int iNum = 0;
while ((iNum = Convert.ToInt32(VcArray.Length * random.NextDouble())) == VcArray.Length)
{
iNum = Convert.ToInt32(VcArray.Length * random.NextDouble());
}
VNum += VcArray[iNum];
}
return VNum;
}
}