基于C#异步套接字的聊天程序DEMO
c#制作的聊天程序,可以实现QQ图像的发送,屏幕截取等QQ版的功能,希望对大家有帮助,仅供学习之用
c#QQ农场偷菜源码
一款不错的C#版农场偷菜源码,仅供学习之用,请勿用来干其他的事情哈,学习的,所以共享
c#无限加载的树形DEMO
C#无限级树形加载,直接运行可查看效果,以后直接放到项目中就可以使用啦,方便大家学习,共享啦
c#邮件发送程序DEMO
一款很不错的邮件群发源码,可以实现邮件的群发,单发
希望对大家有帮助
屏幕任意截取TeboScreen
C#写的一款截取任意屏幕大小的画面,可以保存截取的图片,不错的学习源码,希望对大家有帮助
超强大黑客的任务管理器+C#源代码
c#写的一款很不错的任务管理器,比windows下的还有强大那么一点点,有服务,网络监控等,不错的学习源码
c# 多线程(轮询,等待,回调)操作实例
c# 实现多线程的操作,轮询等待回调等异步操作,适合初学者的源码
C#版模拟钢琴DEMO
c#完全模拟钢琴的效果,可以用键盘操作,一个很不错的源码
Asp.net新闻采集器
新新闻采集
对一个网站进行新闻的采集包括标题.....
ASP.NET绘图(GDI)
ASP.NET使用GDI+制作文字|图片水印
[ 2007-8-21 13:21:00 | By: SHARP_C ]
0
推荐System.Drawing.Image image = System.Drawing.Image.FromFile(@"D:\vista\cmd.jpg");
//注意Image的命名控件是System.Drawing.Image而不是System.Web.UI.HtmlControls.Image
//在等号后不要使用关键字new,直接从文件创建背景图片
System.Drawing.Image sy = System.Drawing.Image.FromFile(@"D:\vista\723131486.jpg");
//创建要作为水印的图片
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(image);
//创建GDI+绘图图面
g.DrawString("本水印由sharp-c制作!", new System.Drawing.Font("隶书", 24), System.Drawing.Brushes.Blue, new System.Drawing.PointF(50, 20));
//在背景图片上绘制水印文字
g.DrawImage(sy,new System.Drawing.Point(400,300));
//在背景图片上绘制水印图片
image.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Jpeg);
//注意:这个很关键,没有就不能显示图片。其中ImageFormat取枚举值
image.Dispose();
g.Dispose();
//销毁对象
效果图如下:
图片上传并按比例缩小
在ASP.NET中上传图片并生成缩略图的C#源码 using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.IO;
using System.Drawing.Imaging;
namespace eMeng.Exam
{
///
/// Thumbnail 的摘要说明。
///
public class Thumbnail : System.Web.UI.Page
{
protected System.Web.UI.WebControls.Label Label1;
protected System.Web.UI.WebControls.Button Button1;
private void Page_Load(object sender, System.EventArgs e)
{
// 在此处放置用户代码以初始化页面
Label1.Text = "在ASP.NET里轻松实炙趼酝?lt;/h3>";
Button1.Text = "上载并显示缩略图";
}
#region Web 窗体设计器生成的代码
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。
//
InitializeComponent();
base.OnInit(e);
}
///
/// 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。
///
private void InitializeComponent()
{
this.Button1.Click += new System.EventHandler(this.Button1_Click);
this.Load += new System.EventHandler(this.Page_Load);
}
#endregion
private void Button1_Click(object sender, System.EventArgs e)
{
HttpFileCollection MyFileColl = HttpContext.Current.Request.Files;
HttpPostedFile MyPostedFile = MyFileColl[0];
if (MyPostedFile.ContentType.ToString().ToLower().IndexOf("image") < 0)
{
Response.Write("无效的图形格式。");
return;
}
GetThumbNail(MyPostedFile.FileName, 100, 100,
MyPostedFile.ContentType.ToString(), false, MyPostedFile.InputStream);
}
private System.Drawing.Imaging.ImageFormat GetImageType(object strContentType)
{
if ((strContentType.ToString().ToLower()) == "image/pjpeg")
{
return System.Drawing.Imaging.ImageFormat.Jpeg;
}
else if ((strContentType.ToString().ToLower()) == "image/gif")
{
return System.Drawing.Imaging.ImageFormat.Gif;
}
else if ((strContentType.ToString().ToLower()) == "image/bmp")
{
return System.Drawing.Imaging.ImageFormat.Bmp;
}
else if ((strContentType.ToString().ToLower()) == "image/tiff")
{
return System.Drawing.Imaging.ImageFormat.Tiff;
}
else if ((strContentType.ToString().ToLower()) == "image/x-icon")
{
return System.Drawing.Imaging.ImageFormat.Icon;
}
else if ((strContentType.ToString().ToLower()) == "image/x-png")
{
return System.Drawing.Imaging.ImageFormat.Png;
}
else if ((strContentType.ToString().ToLower()) == "image/x-emf")
{
return System.Drawing.Imaging.ImageFormat.Emf;
}
else if ((strContentType.ToString().ToLower()) == "image/x-exif")
{
return System.Drawing.Imaging.ImageFormat.Exif;
}
else if ((strContentType.ToString().ToLower()) == "image/x-wmf")
{
return System.Drawing.Imaging.ImageFormat.Wmf;
}
else
{
return System.Drawing.Imaging.ImageFormat.MemoryBmp;
}
}
private void GetThumbNail(string strFileName, int iWidth, int iheight,
string strContentType, bool blnGetFromFile, System.IO.Stream ImgStream)
{
System.Drawing.Image oImg;
if (blnGetFromFile)
{
oImg = System.Drawing.Image.FromFile(strFileName);
}
else
{
oImg = System.Drawing.Image.FromStream(ImgStream);
}
oImg = oImg.GetThumbnailImage(iWidth, iheight, null, IntPtr.Zero);
string strGuid = System.Guid.NewGuid().ToString().ToUpper();
string strFileExt = strFileName.Substring(strFileName.LastIndexOf("."));
Response.ContentType = strContentType;
MemoryStream MemStream = new MemoryStream();
oImg.Save(MemStream, GetImageType(strContentType));
MemStream.WriteTo(Response.OutputStream);
}
}
}
功能:
1。把图片文件(JPG GIF PNG)上传,
2。保存到指定的路径(在web.config中设置路径,以文件的原有格式保存),
3。并自动生成指定宽度的(在web.config中设置宽度)
4。和指定格式的(在web.config中指定缩略图的格式)
5。和原图比例相同的缩略图(根据宽度和原图的宽和高计算所略图的高度)
6。可以判断是否已经存在文件
7。如果不覆盖,则给出错误
8。如果选中"覆盖原图"checkbox,则覆盖原图。
9。可以根据要求,在webform上设置1个以上的file input和相应的checkbox
10。并在文件上传完毕后,显示原图的文件名,尺寸,字节,和
11。缩略图的文件名尺寸。
12。缩略图的文件名格式:原图+"_thumb."+指定格式,如:test.jpg_thumb.gif,以便于管理。
--------------------
public void UploadFile(object sender, System.EventArgs e)
{
string imgNameOnly, imgNameNoExt, imgExt;
string imgThumbnail;
int erroNumber = 0;
System.Drawing.Image oriImg, newImg;
string strFePicSavePath = ConfigurationSettings.AppSettings["FePicSavePath"].ToString();
string strFePicThumbFormat = ConfigurationSettings.AppSettings["FePicThumbFormat"].ToString().ToLower();
int intFeThumbWidth = Int32.Parse(ConfigurationSettings.AppSettings["FePicThumbWidth"]);
string fileExt;
StringBuilder picInfo = new StringBuilder();
if(Page.IsValid)
{
for(int i = 0;i < Request.Files.Count; i++)
{
HttpPostedFile PostedFile = Request.Files[i];
fileExt = (System.IO.Path.GetExtension(PostedFile.FileName)).ToString().ToLower();
imgNameOnly = System.IO.Path.GetFileName(PostedFile.FileName);
if(fileExt == ".jpg" || fileExt == ".gif" || fileExt == ".png")
{
if(System.IO.File.Exists(strFePicSavePath + imgNameOnly) && (checkboxlistRewrite.Items[i].Selected == false))
{
erroNumber = erroNumber + 1;
picInfo.Append("错误:文件("+ (i+1) +") " + imgNameOnly + " 已经存在,请修改文件名" );
}
}
else
{
erroNumber = erroNumber + 1;
picInfo.Append("错误:文件("+ (i+1) +") " + imgNameOnly + " 扩展名 " + fileExt + " 不被许可" );
}
}
if(erroNumber > 0)
{
picInfo.Append("全部操作均未完成,请修改错误,再进行操作");
}
else
{
for(int i = 0;i < Request.Files.Count; i++)
{
HttpPostedFile PostedFile = Request.Files[i];
imgNameOnly = System.IO.Path.GetFileName(PostedFile.FileName);
imgNameNoExt = System.IO.Path.GetFileNameWithoutExtension(PostedFile.FileName);
imgExt = System.IO.Path.GetExtension(PostedFile.FileName).ToString().ToLower();
oriImg = System.Drawing.Image.FromStream(PostedFile.InputStream);
newImg = oriImg.GetThumbnailImage(intFeThumbWidth, intFeThumbWidth * oriImg.Height/oriImg.Width,null,new System.IntPtr(0));
switch(imgExt)
{
//case ".jpeg":
case ".jpg":
oriImg.Save(strFePicSavePath + imgNameOnly , System.Drawing.Imaging.ImageFormat.Jpeg);
break;
case ".gif":
oriImg.Save(strFePicSavePath + imgNameOnly , System.Drawing.Imaging.ImageFormat.Gif);
break;
case ".png":
oriImg.Save(strFePicSavePath + imgNameOnly , System.Drawing.Imaging.ImageFormat.Png);
break;
}
//oriImg.Save(ConfigurationSettings.AppSettings["FePicSavePath"] + imgNameNoExt + ".jpg", System.Drawing.Imaging.ImageFormat.Jpeg);
switch(strFePicThumbFormat)
{
//jpeg format can get the smallest file size, and the png is the largest size
//case "jpeg":
case "jpg":
newImg.Save(strFePicSavePath + imgNameOnly + "_thumb.jpg",System.Drawing.Imaging.ImageFormat.Jpeg);
imgThumbnail = imgNameOnly + "_thumb.jpg";
break;
case "gif":
newImg.Save(strFePicSavePath + imgNameOnly + "_thumb.gif",System.Drawing.Imaging.ImageFormat.Gif);
imgThumbnail = imgNameOnly + "_thumb.gif";
break;
case "png":
newImg.Save(strFePicSavePath + imgNameOnly + "_thumb.png",System.Drawing.Imaging.ImageFormat.Png);
imgThumbnail = imgNameOnly + "_thumb.png";
break;
default:
newImg.Save(strFePicSavePath + imgNameOnly + "_thumb.jpg",System.Drawing.Imaging.ImageFormat.Jpeg);
imgThumbnail = imgNameOnly + "_thumb.jpg";
break;
}//switch
picInfo.Append("文件 名:" + imgNameOnly + " ( " + oriImg.Width + " x " + oriImg.Height + " ) " + PostedFile.ContentLength/1024 + "KB");
picInfo.Append("缩略图名:" + imgThumbnail + " ( " + newImg.Width + " x " + newImg.Height + " )");
oriImg.Dispose();
newImg.Dispose();
}//for
picInfo.Append("所有操作成功");
}// if erronumber = 0
}
else
{
picInfo.Append("有错误,请检查。操作未成功");
}
lblPicInfo.Text = picInfo.ToString();
}
资料引用:http://www.knowsky.com/5723.html