转自:http://www.cnblogs.com/dreamof/archive/2009/01/22/1379822.html
一、验证码简介 验证码功能一般是用于防止批量注册的,不少网站为了防止用户利用机器人自动注册、登录、灌水,都采用了验证码技术。所谓验证码,就是将一串随机产生的数字或字母或符号或文字,生成一幅图片, 图片里加上一些干扰象素(防止OCR),由用户肉眼识别其中的验证码信息,输入表单提交网站验证,验证成功后才能使用某项功能。
常见的验证码有如下几种: 1、纯数字验证码,一般为四位随机数字; 2、数字+字母验证码,一般从数字(0~9)和字母(A~Z和a~z)中随机抽出几个字符组成; 3、汉字验证码,相对而言,这种验证码比较少见一点,实现起来也相对复杂一些,但在不少网站中还是可以看到的;
二、验证码的实现 1、纯数字验证码的实现 纯数字验证码的实现相对比较简单,可通过以下两种方法来实现 (1)使用随机数方式,代码如下:
private String GetRandomint(int codeCount) { Random random =new Random(); string min =""; string max =""; for (int i =0; i < codeCount; i++) { min +="1"; max+="9"; } return (random.Next(Convert.ToInt32(min),Convert.ToInt32(max)).ToString()); }
(2)使用随机组合方式,代码如下:
privatestring CreateRandomCode(int codeCount) { string allChar ="0,1,2,3,4,5,6,7,8,9"; string[] allCharArray = allChar.Split(','); string randomCode =""; int temp =-1; Random rand =new Random(); for (int i =0; i < codeCount; i++) { if (temp !=-1) { rand =new Random(i * temp * ((int)DateTime.Now.Ticks)); } int t = rand.Next(9); if (temp == t) { return CreateRandomCode(codeCount); } temp = t; randomCode += allCharArray[t]; } return randomCode; }
2、数字+字母验证码的实现,代码如下:
privatestring CreateRandomCode(int codeCount) { string allChar ="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,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z"; string[] allCharArray = allChar.Split(','); string randomCode =""; int temp =-1; Random rand =new Random(); for (int i =0; i < codeCount; i++) { if (temp !=-1) { rand =new Random(i * temp * ((int)DateTime.Now.Ticks)); } int t = rand.Next(61); if (temp == t) { return CreateRandomCode(codeCount); } temp = t; randomCode += allCharArray[t]; } return randomCode; }
3、汉字验证码的实现,代码如下:
/**/ /* 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 */ publicstaticobject[] 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 =newobject[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 < strlength; 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); } elseif (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 =newbyte[] { 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; }
/**/ /*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 < strlength; 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); } elseif (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 =newbyte[] { 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; }
三、具体实例 (实例1)
<body> <form id="form1" runat="server"> <div> <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> <asp:Image ID="Image1" runat="server" ImageUrl="png.aspx"/><br /> <br /> <asp:Button ID="Button2" runat="server" OnClick="Button2_Click" Text="Button"/> <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"> <asp:ListItem Value="3">默认</asp:ListItem> <asp:ListItem Value="1">文字</asp:ListItem> <asp:ListItem Value="2">数字</asp:ListItem> <asp:ListItem Value="3">混合</asp:ListItem> </asp:DropDownList></div> </form></body>
protectedvoid DropDownList1_SelectedIndexChanged(object sender, EventArgs e) { switch (DropDownList1.SelectedValue) { case"1": Image1.ImageUrl ="png.aspx?aa=1"; break; case"2": Image1.ImageUrl ="png.aspx?aa=2"; break; case"3": Image1.ImageUrl ="png.aspx?aa=3"; break; } } protectedvoid Button2_Click(object sender, EventArgs e) { if (TextBox1.Text == Session["gif"].ToString()) Response.Write("OK,正确"); else Response.Write("验证码不符合"); }
publicpartialclass png : System.Web.UI.Page { protectedvoid Page_Load(object sender, EventArgs e) { switch (Request.QueryString["aa"]) { case"1": gif = stxt(10); Session["gif"] = stxt(10); break; case"2": gif = GetRandomint(4); Session["gif"] = GetRandomint(4); break; case"3": gif = CreateRandomCode(4); Session["gif"] = CreateRandomCode(4); break; default: gif = CreateRandomCode(4); Session["gif"] = CreateRandomCode(4); break; } CreateImage(Session["gif"].ToString()); }
private String GetRandomint(int codeCount) { Random random =new Random(); string min =""; string max =""; for (int i =0; i < codeCount; i++) { min +="1"; max+="9"; } return (random.Next(Convert.ToInt32(min),Convert.ToInt32(max)).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 */ publicstaticobject[] 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 =newobject[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 < strlength; 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); } elseif (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 =newbyte[] { 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; } privatestring stxt(int num) { Encoding gb = Encoding.GetEncoding("gb2312");
//调用函数产生10个随机中文汉字编码 object[] bytes = CreateRegionCode(num); string strtxt ="";
//根据汉字编码的字节数组解码出中文汉字 for (int i =0; i < num; i++) { strtxt += gb.GetString((byte[])Convert.ChangeType(bytes[i], typeof(byte[]))); } return strtxt; } ///<summary> /// 这个是使用字母,数字混合 ///</summary> ///<param name="VcodeNum"></param> ///<returns></returns> privatestring CreateRandomCode(int codeCount) { string allChar ="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,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z"; string[] allCharArray = allChar.Split(','); string randomCode =""; int temp =-1; Random rand =new Random(); for (int i =0; i < codeCount; i++) { if (temp !=-1) { rand =new Random(i * temp * ((int)DateTime.Now.Ticks)); } int t = rand.Next(61); if (temp == t) { return CreateRandomCode(codeCount); } temp = t; randomCode += allCharArray[t]; } return randomCode; }
privatevoid CreateImage(string checkCode) { int iwidth = (int)(checkCode.Length *20); System.Drawing.Bitmap image =new System.Drawing.Bitmap(iwidth, 25); Graphics g = Graphics.FromImage(image); Font f =new System.Drawing.Font("Arial", 10, System.Drawing.FontStyle.Bold); Brush b =new System.Drawing.SolidBrush(Color.White); //g.FillRectangle(new System.Drawing.SolidBrush(Color.Blue),0,0,image.Width, image.Height); g.Clear(Color.Black); g.DrawString(checkCode, f, b, 3, 3); Pen blackPen =new Pen(Color.Black, 0); Random rand =new Random(); //for (int i=0;i<5;i++) //{ // int y = rand.Next(image.Height); // g.DrawLine(blackPen,0,y,image.W
调用页面前台代码
调用页面后台代码
生成验证码前台文件
生成验证码后台文件
四、效果图展示 验证码数字
验证码数字+字母
验证码汉字
![](https://images.cnblogs.com/cnblogs_com/dreamof/yzm11.jpg)
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private String GetRandomint(int codeCount) { Random random =new Random(); string min =""; string max =""; for (int i =0; i < codeCount; i++) { min +="1"; max+="9"; } return (random.Next(Convert.ToInt32(min),Convert.ToInt32(max)).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 */ publicstaticobject[] 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 =newobject[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 < strlength; 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); } elseif (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 =newbyte[] { 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; } privatestring stxt(int num) { Encoding gb = Encoding.GetEncoding("gb2312");
//调用函数产生10个随机中文汉字编码 object[] bytes = CreateRegionCode(num); string strtxt ="";
//根据汉字编码的字节数组解码出中文汉字 for (int i =0; i < num; i++) { strtxt += gb.GetString((byte[])Convert.ChangeType(bytes[i], typeof(byte[]))); } return strtxt; } ///<summary> /// 这个是使用字母,数字混合 ///</summary> ///<param name="VcodeNum"></param> ///<returns></returns> privatestring CreateRandomCode(int codeCount) { string allChar ="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,a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z"; string[] allCharArray = allChar.Split(','); string randomCode =""; int temp =-1; Random rand =new Random(); for (int i =0; i < codeCount; i++) { if (temp !=-1) { rand =new Random(i * temp * ((int)DateTime.Now.Ticks)); } int t = rand.Next(61); if (temp == t) { return CreateRandomCode(codeCount); } temp = t; randomCode += allCharArray[t]; } return randomCode; }
privatevoid CreateImage(string checkCode) { int iwidth = (int)(checkCode.Length *20); System.Drawing.Bitmap image =new System.Drawing.Bitmap(iwidth, 25); Graphics g = Graphics.FromImage(image); Font f =new System.Drawing.Font("Arial", 10, System.Drawing.FontStyle.Bold); Brush b =new System.Drawing.SolidBrush(Color.White); //g.FillRectangle(new System.Drawing.SolidBrush(Color.Blue),0,0,image.Width, image.Height); g.Clear(Color.Black); g.DrawString(checkCode, f, b, 3, 3); Pen blackPen =new Pen(Color.Black, 0); Random rand =new Random(); //for (int i=0;i<5;i++) //{ // int y = rand.Next(image.Height); // g.DrawLine(blackPen,0,y,image.W
(实例2):20101018续加
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<script language="Javascript"> function Regist() { var url =""; url ="/GZPI/Service/Registry/ViewProtocol.aspx"; window.open(url); returnfalse; } function LoginClick() { if(document.Login.UserName.value =="") { alert("用户名不能为空!"); returnfalse; } document.Login.submit(); document.Login.Password.value =""; returnfalse; } function f_refreshtype() { var Image1 = document.getElementById("IMGCheckCode"); if (Image1 !=null) { Image1.src = Image1.src +"?"; } } </script> <TABLE cellSpacing="0" cellPadding="5" width="100%" border="0"> <TR> <TD class="fontblack" align="right" width="30%">用 户 名:</TD> <TD vAlign="bottom" align="left" width="62%"><input id="Text1" style="BORDER-RIGHT: #43a7e2 1px solid; BORDER-TOP: #43a7e2 1px solid; BACKGROUND: #fcfcfc; BORDER-LEFT: #43a7e2 1px solid; BORDER-BOTTOM: #43a7e2 1px solid" size="13" name="UserName" width="100px"> </TD> </TR> <TR> <TD class="fontblack" align="right" height="23">密 码:</TD> <TD vAlign="bottom" align="left" height="23"><input id="Password1" style="BORDER-RIGHT: #43a7e2 1px solid; BORDER-TOP: #43a7e2 1px solid; BACKGROUND: #fcfcfc; BORDER-LEFT: #43a7e2 1px solid; BORDER-BOTTOM: #43a7e2 1px solid" type="password" size="13" name="Password" width="100px"> </TD> </TR> <TR> <TD class="fontblack" align="right" height="23">校 验 码:</TD> <TD valign="top" align="left" height="23"><FONT face="宋体"><INPUT id="CheckCode" style="BORDER-RIGHT: #43a7e2 1px solid; BORDER-TOP: #43a7e2 1px solid; BACKGROUND: #fcfcfc; BORDER-LEFT: #43a7e2 1px solid; BORDER-BOTTOM: #43a7e2 1px solid" width="100px" size="13" name="CheckCode"> </FONT><a style="CURSOR: hand" onclick="f_refreshtype()" title="看不清楚?点击获取新的校验码!" border="0"><IMG id="IMGCheckCode" src="../GenerateCheckCode.aspx"></a> </TD> </TR> <TR vAlign="bottom" align="center"> <TD class="dlbuttom" colSpan="2" height="23"><input id="Image1" style="CURSOR: hand" onclick="return LoginClick();" tabIndex="3" type="image" height="17" width="55" src="images/login.gif" border="0" name="OkButton"> <input type="image" onClick="return Regist();" border='0' src='images/zuce.gif' width='55' height='17' ID="Image2" NAME="Image2"> </TD> </TR> </TABLE>
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private void OK_Click(object sender, System.EventArgs e) { if (!CheckCodeSame(CheckCode.Text.Trim())) { System.Web.HttpContext.Current.Response.Write("<Script Language='JavaScript'>window.alert('校验码错误!请重新输入!');window.close();</script>"); return; } int userType = 1; try { userType = int.Parse(UserType.Text); } catch { }
GatewayManager gateway = new GatewayManager(corpCode.Text,collegeCode.Text,chargeCode.Text,userName.Text,password.Text,userType); gateway.Login(this); }
/// <summary> /// 判断输入的校验码是否正确 /// </summary> /// <param name="checkCode"></param> /// <returns></returns> public static bool CheckCodeSame(string checkCode) { bool bSame = false; ;
if (HttpContext.Current.Session["CheckCode"] != null) { if (checkCode.ToUpper() == HttpContext.Current.Session["CheckCode"].ToString().ToUpper()) { bSame = true; } } return bSame; }
GatewayManager gateway = new GatewayManager(corpCode.Text,collegeCode.Text,chargeCode.Text,userName.Text,password.Text,userType); gateway.Login(this); }
/// <summary> /// 判断输入的校验码是否正确 /// </summary> /// <param name="checkCode"></param> /// <returns></returns> public static bool CheckCodeSame(string checkCode) { bool bSame = false; ;
if (HttpContext.Current.Session["CheckCode"] != null) { if (checkCode.ToUpper() == HttpContext.Current.Session["CheckCode"].ToString().ToUpper()) { bSame = true; } } return bSame; }
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<HTML> <HEAD> <title>GenerateCheckCode</title> <meta name="GENERATOR" Content="Microsoft Visual Studio .NET 7.1"> <meta name="CODE_LANGUAGE" Content="C#"> <meta name="vs_defaultClientScript" content="JavaScript"> <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5"> </HEAD> <body> <form id="form1" runat="server"> <div><FONT face="宋体"></FONT> </div> </form> </body></HTML>
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using System; using System.Collections; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Drawing; using System.Drawing.Drawing2D;
namespace GZPI.Gateway { ///<summary> /// GenerateCheckCode 的摘要说明。 ///</summary> publicclass GenerateCheckCode : System.Web.UI.Page { privatevoid Page_Load(object sender, System.EventArgs e) { // 在此处放置用户代码以初始化页面 this.CreateCheckCodeImage(GenerateCheckCodes(4)); }
#region Web 窗体设计器生成的代码 overrideprotectedvoid OnInit(EventArgs e) { // // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。 // InitializeComponent(); base.OnInit(e); } ///<summary> /// 设计器支持所需的方法 - 不要使用代码编辑器修改 /// 此方法的内容。 ///</summary> privatevoid InitializeComponent() { this.Load +=new System.EventHandler(this.Page_Load); } #endregion
privatestring GenerateCheckCodes(int iCount) { int number; string checkCode = String.Empty; int iSeed = DateTime.Now.Millisecond; System.Random random =new Random(iSeed); for (int i =0; i < iCount; i++) { number = random.Next(10); checkCode += number.ToString(); }
Session["CheckCode"] = checkCode; return checkCode; }
privatevoid CreateCheckCodeImage(string checkCode) { if (checkCode ==null|| checkCode.Trim() == String.Empty) return; int iWordWidth =15; int iImageWidth = checkCode.Length * iWordWidth; Bitmap image =new Bitmap(iImageWidth, 20); Graphics g = Graphics.FromImage(image); try { //生成随机生成器 Random random =new Random(); //清空图片背景色 g.Clear(Color.White);
//画图片的背景噪音点 for (int i =0; i <20; i++) { int x1 = random.Next(image.Width); int x2 = random.Next(image.Width); int y1 = random.Next(image.Height); int y2 = random.Next(image.Height); g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2); }
//画图片的背景噪音线 for (int i =0; i <2; i++) { int x1 =0; int x2 = image.Width; int y1 = random.Next(image.Height); int y2 = random.Next(image.Height); if (i ==0) { g.DrawLine(new Pen(Color.Gray, 2), x1, y1, x2, y2); } }
for (int i =0; i < checkCode.Length; i++) {
string Code = checkCode[i].ToString(); int xLeft = iWordWidth * (i); random =new Random(xLeft); int iSeed = DateTime.Now.Millisecond; int iValue = random.Next(iSeed) %4; if (iValue ==0) { Font font =new Font("Arial", 13, (FontStyle.Bold | System.Drawing.FontStyle.Italic)); Rectangle rc =new Rectangle(xLeft, 0, iWordWidth, image.Height); LinearGradientBrush brush =new LinearGradientBrush(rc, Color.Blue, Color.Red, 1.5f, true); g.DrawString(Code, font, brush, xLeft, 2); } elseif (iValue ==1) { Font font =new System.Drawing.Font("楷体", 13, (FontStyle.Bold)); Rectangle rc =new Rectangle(xLeft, 0, iWordWidth, image.Height); LinearGradientBrush brush =new LinearGradientBrush(rc, Color.Blue, Color.DarkRed, 1.3f, true); g.DrawString(Code, font, brush, xLeft, 2); } elseif (iValue ==2) { Font font =new System.Drawing.Font("宋体", 13, (System.Drawing.FontStyle.Bold)); Rectangle rc =new Rectangle(xLeft, 0, iWordWidth, image.Height); LinearGradientBrush brush =new LinearGradientBrush(rc, Color.Green, Color.Blue, 1.2f, true); g.DrawString(Code, font, brush, xLeft, 2); } elseif (iValue ==3) { Font font =new System.Drawing.Font("黑体", 13, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Bold)); Rectangle rc =new Rectangle(xLeft, 0, iWordWidth, image.Height); LinearGradientBrush brush =new LinearGradientBrush(rc, Color.Blue, Color.Green, 1.8f, true); g.DrawString(Code, font, brush, xLeft, 2); } } //////画图片的前景噪音点 //for (int i = 0; i < 8; i++) //{ // int x = random.Next(image.Width); // int y = random.Next(image.Height); // image.SetPixel(x, y, Color.FromArgb(random.Next())); //} //画图片的边框线 g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width -1, image.Height -1); System.IO.MemoryStream ms =new System.IO.MemoryStream(); image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif); Response.ClearContent();
Response.BinaryWrite(ms.ToArray()); } finally { g.Dispose(); image.Dispose(); } } } }
namespace GZPI.Gateway { ///<summary> /// GenerateCheckCode 的摘要说明。 ///</summary> publicclass GenerateCheckCode : System.Web.UI.Page { privatevoid Page_Load(object sender, System.EventArgs e) { // 在此处放置用户代码以初始化页面 this.CreateCheckCodeImage(GenerateCheckCodes(4)); }
#region Web 窗体设计器生成的代码 overrideprotectedvoid OnInit(EventArgs e) { // // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。 // InitializeComponent(); base.OnInit(e); } ///<summary> /// 设计器支持所需的方法 - 不要使用代码编辑器修改 /// 此方法的内容。 ///</summary> privatevoid InitializeComponent() { this.Load +=new System.EventHandler(this.Page_Load); } #endregion
privatestring GenerateCheckCodes(int iCount) { int number; string checkCode = String.Empty; int iSeed = DateTime.Now.Millisecond; System.Random random =new Random(iSeed); for (int i =0; i < iCount; i++) { number = random.Next(10); checkCode += number.ToString(); }
Session["CheckCode"] = checkCode; return checkCode; }
privatevoid CreateCheckCodeImage(string checkCode) { if (checkCode ==null|| checkCode.Trim() == String.Empty) return; int iWordWidth =15; int iImageWidth = checkCode.Length * iWordWidth; Bitmap image =new Bitmap(iImageWidth, 20); Graphics g = Graphics.FromImage(image); try { //生成随机生成器 Random random =new Random(); //清空图片背景色 g.Clear(Color.White);
//画图片的背景噪音点 for (int i =0; i <20; i++) { int x1 = random.Next(image.Width); int x2 = random.Next(image.Width); int y1 = random.Next(image.Height); int y2 = random.Next(image.Height); g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2); }
//画图片的背景噪音线 for (int i =0; i <2; i++) { int x1 =0; int x2 = image.Width; int y1 = random.Next(image.Height); int y2 = random.Next(image.Height); if (i ==0) { g.DrawLine(new Pen(Color.Gray, 2), x1, y1, x2, y2); } }
for (int i =0; i < checkCode.Length; i++) {
string Code = checkCode[i].ToString(); int xLeft = iWordWidth * (i); random =new Random(xLeft); int iSeed = DateTime.Now.Millisecond; int iValue = random.Next(iSeed) %4; if (iValue ==0) { Font font =new Font("Arial", 13, (FontStyle.Bold | System.Drawing.FontStyle.Italic)); Rectangle rc =new Rectangle(xLeft, 0, iWordWidth, image.Height); LinearGradientBrush brush =new LinearGradientBrush(rc, Color.Blue, Color.Red, 1.5f, true); g.DrawString(Code, font, brush, xLeft, 2); } elseif (iValue ==1) { Font font =new System.Drawing.Font("楷体", 13, (FontStyle.Bold)); Rectangle rc =new Rectangle(xLeft, 0, iWordWidth, image.Height); LinearGradientBrush brush =new LinearGradientBrush(rc, Color.Blue, Color.DarkRed, 1.3f, true); g.DrawString(Code, font, brush, xLeft, 2); } elseif (iValue ==2) { Font font =new System.Drawing.Font("宋体", 13, (System.Drawing.FontStyle.Bold)); Rectangle rc =new Rectangle(xLeft, 0, iWordWidth, image.Height); LinearGradientBrush brush =new LinearGradientBrush(rc, Color.Green, Color.Blue, 1.2f, true); g.DrawString(Code, font, brush, xLeft, 2); } elseif (iValue ==3) { Font font =new System.Drawing.Font("黑体", 13, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Bold)); Rectangle rc =new Rectangle(xLeft, 0, iWordWidth, image.Height); LinearGradientBrush brush =new LinearGradientBrush(rc, Color.Blue, Color.Green, 1.8f, true); g.DrawString(Code, font, brush, xLeft, 2); } } //////画图片的前景噪音点 //for (int i = 0; i < 8; i++) //{ // int x = random.Next(image.Width); // int y = random.Next(image.Height); // image.SetPixel(x, y, Color.FromArgb(random.Next())); //} //画图片的边框线 g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width -1, image.Height -1); System.IO.MemoryStream ms =new System.IO.MemoryStream(); image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif); Response.ClearContent();
Response.BinaryWrite(ms.ToArray()); } finally { g.Dispose(); image.Dispose(); } } } }
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