随机更换验证码代码 我现在再做一个项目,遇到了一个需要在页面设计上面写一段javascript脚本代码,没办法往下写了,所以在此求助!! 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 <script type="text/javascript"> function show(im) { im.src="ValidateCode1.aspx?"+new Date; } </script>ValidateCode1.aspx为验证码文件<img src="ValidateCode1.aspx" onclick ="show(this)" /></td> 调用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;using System.ComponentModel;using System.Web.SessionState;public partial class ValidateCode1 : System.Web.UI.Page{ protected void Page_Load(object sender, EventArgs e) { string randomcode = this.CreateRandomCode(4); Session["CheckCode"] = randomcode; //ViewState["ValidateCode"] = randomcode; this.CreateImage(randomcode); } private string CreateRandomCode(int length) { int rand; char code; string randomcode = String.Empty; //生成一定长度的验证码 System.Random random = new Random(); for (int i = 0; i < length; i++) { rand = random.Next(); if (rand % 3 == 0) { code = (char)('A' + (char)(rand % 26)); } else { code = (char)('0' + (char)(rand % 10)); } randomcode += code.ToString(); } return randomcode; } /// <summary> /// 创建随机码图片 /// </summary> /// <param name="randomcode">随机码</param> private void CreateImage(string randomcode) { int randAngle = 45; //随机转动角度 int mapwidth = (int)(randomcode.Length * 23); Bitmap map = new Bitmap(mapwidth, 28);//创建图片背景 Graphics graph = Graphics.FromImage(map); graph.Clear(Color.White);//清除画面,填充背景 graph.DrawRectangle(new Pen(Color.White, 0), 0, 0, map.Width - 1, map.Height - 1);//画一个边框 //graph.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;//模式 Random rand = new Random(); //背景噪点生成 Pen blackPen = new Pen(Color.LightGray, 0); for (int i = 0; i < 50; i++) { int x = rand.Next(0, map.Width); int y = rand.Next(0, map.Height); graph.DrawRectangle(blackPen, x, y, 1, 1); } //验证码旋转,防止机器识别 char[] chars = randomcode.ToCharArray();//拆散字符串成单字符数组 //文字距中 StringFormat format = new StringFormat(StringFormatFlags.NoClip); format.Alignment = StringAlignment.Center; format.LineAlignment = StringAlignment.Center; //定义颜色 Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple }; //定义字体 string[] font = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" }; for (int i = 0; i < chars.Length; i++) { int cindex = rand.Next(7); int findex = rand.Next(5); Font f = new System.Drawing.Font(font[findex], 13, System.Drawing.FontStyle.Bold);//字体样式(参数2为字体大小) Brush b = new System.Drawing.SolidBrush(c[cindex]); Point dot = new Point(16, 16); //graph.DrawString(dot.X.ToString(),fontstyle,new SolidBrush(Color.Black),10,150);//测试X坐标显示间距的 float angle = rand.Next(-randAngle, randAngle);//转动的度数 graph.TranslateTransform(dot.X, dot.Y);//移动光标到指定位置 graph.RotateTransform(angle); graph.DrawString(chars[i].ToString(), f, b, 1, 1, format); //graph.DrawString(chars[i].ToString(),fontstyle,new SolidBrush(Color.Blue),1,1,format); graph.RotateTransform(-angle);//转回去 graph.TranslateTransform(2, -dot.Y);//移动光标到指定位置 } //生成图片 System.IO.MemoryStream ms = new System.IO.MemoryStream(); map.Save(ms, System.Drawing.Imaging.ImageFormat.Gif); Response.ClearContent(); Response.ContentType = "image/gif"; Response.BinaryWrite(ms.ToArray()); graph.Dispose(); map.Dispose(); }} 做这样一个网页大概要多久时间? asp.net循环得到月份?在线等 错误: 属性“WebForm_AutoFocus”的值为 null、未定义或不是 Function 对象 .Net DataList取行数的问题 如何得到SELECT查询语句得到的结果的行数 生成静态页面有哪些好处? passport登录问题, 急。。。 怎么在vs.net中实现DW中的模板功能? 显示文章内容用什么控件好? crystal report中如何改变报表宽度 100分 VS2008属性窗口位置问题 急!!!求ajax动态绑定下拉列表的两级联动代码
function show(im)
{
im.src="ValidateCode1.aspx?"+new Date;
}
</script>
ValidateCode1.aspx为验证码文件
<img src="ValidateCode1.aspx" onclick ="show(this)" /></td> 调用
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;
using System.ComponentModel;
using System.Web.SessionState;public partial class ValidateCode1 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
string randomcode = this.CreateRandomCode(4);
Session["CheckCode"] = randomcode;
//ViewState["ValidateCode"] = randomcode;
this.CreateImage(randomcode);
}
private string CreateRandomCode(int length)
{
int rand;
char code;
string randomcode = String.Empty; //生成一定长度的验证码
System.Random random = new Random();
for (int i = 0; i < length; i++)
{
rand = random.Next(); if (rand % 3 == 0)
{
code = (char)('A' + (char)(rand % 26));
}
else
{
code = (char)('0' + (char)(rand % 10));
} randomcode += code.ToString();
}
return randomcode;
}
/// <summary>
/// 创建随机码图片
/// </summary>
/// <param name="randomcode">随机码</param>
private void CreateImage(string randomcode)
{
int randAngle = 45; //随机转动角度
int mapwidth = (int)(randomcode.Length * 23);
Bitmap map = new Bitmap(mapwidth, 28);//创建图片背景
Graphics graph = Graphics.FromImage(map);
graph.Clear(Color.White);//清除画面,填充背景
graph.DrawRectangle(new Pen(Color.White, 0), 0, 0, map.Width - 1, map.Height - 1);//画一个边框
//graph.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;//模式
Random rand = new Random(); //背景噪点生成
Pen blackPen = new Pen(Color.LightGray, 0);
for (int i = 0; i < 50; i++)
{
int x = rand.Next(0, map.Width);
int y = rand.Next(0, map.Height);
graph.DrawRectangle(blackPen, x, y, 1, 1);
}
//验证码旋转,防止机器识别
char[] chars = randomcode.ToCharArray();//拆散字符串成单字符数组 //文字距中
StringFormat format = new StringFormat(StringFormatFlags.NoClip);
format.Alignment = StringAlignment.Center;
format.LineAlignment = StringAlignment.Center; //定义颜色
Color[] c = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };
//定义字体
string[] font = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" }; for (int i = 0; i < chars.Length; i++)
{
int cindex = rand.Next(7);
int findex = rand.Next(5); Font f = new System.Drawing.Font(font[findex], 13, System.Drawing.FontStyle.Bold);//字体样式(参数2为字体大小)
Brush b = new System.Drawing.SolidBrush(c[cindex]); Point dot = new Point(16, 16);
//graph.DrawString(dot.X.ToString(),fontstyle,new SolidBrush(Color.Black),10,150);//测试X坐标显示间距的
float angle = rand.Next(-randAngle, randAngle);//转动的度数 graph.TranslateTransform(dot.X, dot.Y);//移动光标到指定位置
graph.RotateTransform(angle);
graph.DrawString(chars[i].ToString(), f, b, 1, 1, format);
//graph.DrawString(chars[i].ToString(),fontstyle,new SolidBrush(Color.Blue),1,1,format);
graph.RotateTransform(-angle);//转回去
graph.TranslateTransform(2, -dot.Y);//移动光标到指定位置
}
//生成图片
System.IO.MemoryStream ms = new System.IO.MemoryStream();
map.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
Response.ClearContent();
Response.ContentType = "image/gif";
Response.BinaryWrite(ms.ToArray());
graph.Dispose();
map.Dispose(); }
}