验证码

新建一个页面image.aspx,添加命名空间： using System.Drawing.Imaging; using System.IO; using System.Drawing； 然后在Page_load事件拷入如下代码： //生成4位的验证码 string tmp = RndNum(4); HttpCookie a = new HttpCookie(“ImageV”,tmp); Response.Cookies.Add(a); this.ValidateCode(tmp); 接下来向该页面添加两个方法： private void ValidateCode(string VNum) { Bitmap Img=null; Graphics g=null; MemoryStream ms=null; int gheight=VNum.Length*12; Img=new Bitmap(gheight,25); g=Graphics.FromImage(Img); //背景颜色 g.Clear(Color.White); //文字字体 Font f=new Font(“Arial Black”,10); //文字颜色 SolidBrush s=new SolidBrush(Color.Black); g.DrawString(VNum,f,s,3,3); ms=new MemoryStream(); Img.Save(ms,ImageFormat.Jpeg); Response.ClearContent(); Response.ContentType='image/Jpeg'; Response.BinaryWrite(ms.ToArray()); g.Dispose(); Img.Dispose(); Response.End(); } private 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,v,w,x,y,z'; string[] VcArray=Vchar.Split(new Char [] {','}); string VNum=””; int temp=-1; Random rand=new Random(); for(int i=1;i