如何生成.net验证码

1,在TextVerfiy.aspx.cs中写入以下代码

using System;
'vw-B(Cx jB9Fo7A1J0using System.Data;51Testing软件测试网U7bx"Pi
using System.Configuration;
Q |2C\-G:x&Ca0using System.Collections;
7Qp'g~#}A1p,Z0using System.Web;51Testing软件测试网|a&\] {[y1B-t
using System.Web.Security;
O4H*YDvToK0using System.Web.UI;
3g1EziGWJ#{0using System.Web.UI.WebControls;
!\:B/B Z%rHo"T0using System.Web.UI.WebControls.WebParts;51Testing软件测试网.l,AlP8C
using System.Web.UI.HtmlControls;
S^s Yad$e;i0using System.Drawing;51Testing软件测试网7X]
}w;~'p4B5|O

public partial class TextVerfiy : System.Web.UI.Page51Testing软件测试网LbFS)UY\
{
tJ+O`S0    protected void Page_Load(object sender, EventArgs e)51Testing软件测试网H^h(Y4BW3wK:w
    {
FTv/D.C0\uvG0        //显示验证码51Testing软件测试网BgS#W2t-J
        this.GenImg(this.GenCode(5));51Testing软件测试网\'}9Za_yU
        //将验证码存储到session中,以便在需要时进行验证51Testing软件测试网r ?j2E?
        Session["image"] = this.GenCode(5);51Testing软件测试网q!u\O`/V-H5Z!N+|
    }51Testing软件测试网!yp9vg8J*l
    //生成5位数的字符51Testing软件测试网a k;JJ8D.} A
    private string GenCode(int num)51Testing软件测试网b*}O^%_ o
    {
Yijo_0        //定义一个验证码数组
Cv{` o+T'{ M0        string[] source ={ "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", "V", "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" };
J-Ez{+T:j{0        string code = "";
4|sr_d;yZ:miv0       
3G AlI[#]
O0        //创建random类51Testing软件测试网)F5Y&X&_.lq:G
        Random rd = new Random();51Testing软件测试网:l4w}6_:MV5g7D Z
        //循环获取验证码
)YK%T$lmy5W0        for (int i = 0; i < num; i++)
\Vi U,k W'h0        {51Testing软件测试网 gC/NI^)Nb
            code+=source[rd.Next(0,source.Length)];
:`.Em|%]3~8su0        }51Testing软件测试网%a(I2BQ"SRE
        return code;51Testing软件测试网2I-S|^ h%@)O
    }51Testing软件测试网vvLN,{}
    //生成图片
s
_6O{.uF)r0    private void GenImg(string code)
"eua4E%O0`0    {
`(mQ[
{1c:V0        //定义画布
T\2YOp0        Bitmap myPalatte = new Bitmap(60, 35);51Testing软件测试网1V;g1gK%Lp
        //在画板上定义绘图的实例
rn\$@(o*HXu0        Graphics gh = Graphics.FromImage(myPalatte);51Testing软件测试网b0b)Q\%g"a9z8q
        //定义矩形
|smp-`B/W0        Rectangle rc = new Rectangle(0, 0, 60, 35);51Testing软件测试网:C9B0M(r7WO [5G
        //填充矩形
,~nfDwf8n0        gh.FillRectangle(new SolidBrush(Color.White), rc);
!DfY4`8i0        //在矩形中画出字符串51Testing软件测试网PGVQ T5|j
        gh.DrawString(code, new Font("宋体", 13), new SolidBrush(Color.Black), rc);51Testing软件测试网c[guw5k
        //将图片显示出来51Testing软件测试网#q5_@A6v9z,Tpdc
        myPalatte.Save(Response.OutputStream,System.Drawing.Imaging.ImageFormat.Jpeg);
!X]1s;S8P6]U)[0        gh.Dispose();
G}k:H4tiV0        myPalatte.Dispose();
_/yG5p9[Z(S.Qh0    }
2hK Yk&h-?3W-}0}51Testing软件测试网?7kh8L+ExtT9G1d

2,在Default.aspx.cs中主要写入以下代码:

using System;
Bs!bo&d Z0using System.Data;
\P'n1NC0using System.Configuration;51Testing软件测试网)^;\JH| g
using System.Web;

O S
Ysn%j)R ]A*P*U0using System.Web.Security;
T']'?/l` gT7j5g1qq#A0using System.Web.UI;
5vIIy^t
Q0using System.Web.UI.WebControls;51Testing软件测试网RP*Xcd8s1C%tW
using System.Web.UI.WebControls.WebParts;51Testing软件测试网&m~]C#|
using System.Web.UI.HtmlControls;

bw9D r1O3gw7q7W0public partial class _Default : System.Web.UI.Page 51Testing软件测试网 l*aZ"kL7};w1a:A(r
{
i/}/J0t8uBA0    protected void Page_Load(object sender, EventArgs e)51Testing软件测试网3IdE6}/sq
    {51Testing软件测试网PLO9L]m:U!b

        //前台定义一个ImageButton按钮,调用1中的页面
%y@9[/l,oh0        ImageButton1.ImageUrl = "TextVerfiy.aspx";
$`xE5Hd+ODa0    }
"B+Yat$@1LgEJ0}
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