asp.net產生驗證碼代碼（純中文）

using System; using System.Data; using System.Configuration; 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.Text; //添加引用 using System.Drawing; //添加引用 /// <summary> /// CheckCode_Ch 的摘要說明 /// </summary> public class CheckCode_Ch { public CheckCode_Ch() { // // TODO: 在此處添加建構函式邏輯 // } private static object[] CreateString() { //定義一個數組儲存漢字編碼的組成元素 string[] str = new string[16] { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" }; Random ran = new Random(); //定義一個隨機數對象 object[] bytes = new object[4]; for (int i = 0; i < 4; i++) { //擷取區位碼第一位 int ran1 = ran.Next(11, 14); string str1 = str[ran1].Trim(); //擷取區位碼第二位並防止資料重複 ran = new Random(ran1 * unchecked((int)DateTime.Now.Ticks) + i); int ran2; if (ran1 == 13) { ran2 = ran.Next(0, 7); } else { ran2 = ran.Next(0, 16); } string str2 = str[ran2].Trim(); //擷取區位碼第三位 ran = new Random(ran2 * unchecked((int)DateTime.Now.Ticks) + i); int ran3 = ran.Next(10, 16); string str3 = str[ran3].Trim(); //擷取區位碼第四位 ran = new Random(ran3 * unchecked((int)DateTime.Now.Ticks) + i); int ran4; if (ran3 == 10) { ran4 = ran.Next(1, 16); } else if (ran3 == 15) { ran4 = ran.Next(0, 15); } else { ran4 = ran.Next(0, 16); } string str4 = str[ran4].Trim(); //定義位元組變數儲存產生的隨機漢字區位碼 byte byte1 = Convert.ToByte(str1 + str2, 16); byte byte2 = Convert.ToByte(str3 + str4, 16); byte[] stradd = new byte[] { byte1, byte2 }; //將產生的漢字位元組放入數組 bytes.SetValue(stradd, i); } return bytes; } private static string GetString() { Encoding gb = Encoding.GetEncoding("gb2312"); object[] bytes = CreateString(); //根據漢字位元組解碼出中文漢字 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[]))); string str = str1 + str2 + str3 + str4; HttpContext.Current.Response.Cookies.Add(new HttpCookie("CheckCode", str)); return str; } public static void GraphicsImage() { System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((GetString().Length * 22.5)), 22); Graphics g = Graphics.FromImage(image); //建立畫布 try { //產生隨機產生器 Random random = new Random(); //清空圖片背景色 g.Clear(Color.White); //畫圖片的背景雜音線 for (int i = 0; i < 1; 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.Black), x1, y1, x2, y2); } Font font = new System.Drawing.Font("Couriew New", 12, System.Drawing.FontStyle.Bold); System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush (new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true); g.DrawString(GetString(), font, brush, 2, 2); //畫圖片的前景噪音點 for (int i = 0; i < 50; i++) { int x = random.Next(image.Width); int y = random.Next(image.Height); image.SetPixel(x, y, Color.FromArgb(random.Next())); } //畫圖片的邊框線 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); HttpContext.Current.Response.ClearContent(); HttpContext.Current.Response.ContentType = "image/Gif"; HttpContext.Current.Response.BinaryWrite(ms.ToArray()); } catch (Exception ms) { HttpContext.Current.Response.Write(ms.Message); } } }

第二步建立一個頁面引用類庫ChineseCheckCode.aspx前台不用寫代碼，後台引用類庫。。

using System; using System.Collections; using System.Configuration; using System.Data; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.HtmlControls; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; public partial class UserValidator_ChineseCheckCode : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { CheckCode_Ch.GraphicsImage(); //調用方法產生四位漢字驗證碼 } }

第三步引用驗證碼頁

<asp:TextBox ID="Validator" runat="server" Width="150px" ></asp:TextBox> <img id="Img1" alt="看不清，請點擊我！" onclick="this.src=this.src+'?'" src="ChineseCheckCode.aspx" style="width: 75px; height: 24px" align="left" /> <asp:ImageButton ID="imgBtnLogin" runat="server" ImageUrl="~/Images/Login.GIF" OnClick="imgBtnLogin_Click" />

後台判斷

protected void imgBtnLogin_Click(object sender, ImageClickEventArgs e) { HttpCookie cookie = Request.Cookies["CheckCode"]; if (cookie.Value == this.Validator.Text.Trim()) { //。。。 } else { Response.Write("<script>alert('驗證碼輸入錯誤，請重新輸入！');Location='ChineseCodeValidator.aspx'</script>"); return; } }

以上驗證碼產生四位，請各位根據 情況做適當修改。
現在總結了產生純數字、數字字母混合、純漢字的驗證碼技術。希望對各位有所協助。。