c#的asp.net上传图片加水印并生成缩略图 文件名 时间

前台UpPicture.aspx代码：
<%@ Page language="c#" Codebehind="UpPicture.aspx.cs" AutoEventWireup="false" Inherits="UpPic.UpPicture" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
    <HEAD>
        <title>UpPicture</title>
        <meta name="GENERATOR" Content="Microsoft Visual Studio .NET 7.1">
        <meta name="CODE_LANGUAGE" Content="C#">
        <meta name="vs_defaultClientScript" content="JavaScript">
        <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5">
    </HEAD>
    <body MS_POSITIONING="GridLayout">
        <form id="Form1" method="post" runat="server">
            <INPUT id="File1" style="Z-INDEX: 101; LEFT: 24px; WIDTH: 440px; POSITION: absolute; TOP: 32px; HEIGHT: 22px"
                type="file" size="54" name="File1" runat="server">
            <asp:Button id="btnUpPic" style="Z-INDEX: 102; LEFT: 472px; POSITION: absolute; TOP: 32px" runat="server"
                Text="上传图片"></asp:Button>
            <asp:Label id="Label1" style="Z-INDEX: 103; LEFT: 24px; POSITION: absolute; TOP: 64px" runat="server"
                Width="520px"></asp:Label>
            <asp:Image id="showSmallPic" style="Z-INDEX: 104; LEFT: 32px; POSITION: absolute; TOP: 104px"
                runat="server"></asp:Image>
        </form>
    </body>
</HTML>

后台UpPicture.aspx.cs代码：
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.Data.SqlClient;
using System.IO;
namespace UpPic
{
    /// <summary>
    /// UpPicture 的摘要说明。
    /// </summary>
    public class UpPicture : System.Web.UI.Page
    {
        protected System.Web.UI.HtmlControls.HtmlInputFile File1;
        protected System.Web.UI.WebControls.Label Label1;
        protected System.Web.UI.WebControls.Image showSmallPic;
        protected System.Web.UI.WebControls.Button btnUpPic;
    
        private void Page_Load(object sender, System.EventArgs e)
        {
            // 在此处放置用户代码以初始化页面
        }

        Web 窗体设计器生成的代码
        //提供一个回调方法,用于确定Image对象在执行生成缩略图操作时何时提前取消执行
        //如果此方法确定 GetThumbnailImage 方法应提前停止执行，则返回 true；否则返回 false
        System.Drawing.Image.GetThumbnailImageAbort callb = null;
        //定义image类的对象
        System.Drawing.Image image,smallImage,shuiyinImg,FlagImage;
        private void btnUpPic_Click(object sender, System.EventArgs e)
        {
            if(this.File1.PostedFile.FileName!="")
            {
                //先取得上传的总路径
                string imagePath=this.File1.PostedFile.FileName;
                //取得图片类型
                string imageType=Path.GetExtension(imagePath).ToUpper();
                //取得图片名称
                string imageName=imagePath.Substring(imagePath.LastIndexOf("\\")+1);
                imageName=System.DateTime.Now.ToString("yyyyMMddhhmmss")+"_"+imageName;
                //判断上传图片类型
                if(imageType==".JPG"||imageType==".BMP"||imageType==".JPEG")
                {
                    //保存原图
                    string ImgPath=Server.MapPath("upFile"+"\\"+imageName);
                    this.File1.PostedFile.SaveAs(ImgPath);
                    //为上传的图片建立引用
                    image=System.Drawing.Image.FromFile(ImgPath);            
                    /*************加水印开始*********************************************/
                    shuiyinImg=System.Drawing.Image.FromFile(Server.MapPath(".")+"/Flag200_100.png");
                    Graphics g = Graphics.FromImage(image);
                    g.DrawImage(shuiyinImg, new Rectangle(image.Width-shuiyinImg.Width, image.Height-shuiyinImg.Height,
                        shuiyinImg.Width, shuiyinImg.Height), 0, 0, shuiyinImg.Width, shuiyinImg.Height, GraphicsUnit.Pixel);
                    g.Dispose();
                    string path1=Server.MapPath("upFile"+"\\Flag_"+imageName);
                    image.Save(path1);
                    image.Dispose();
                    /************加水印的过程结束*********************************************/
                    FlagImage=System.Drawing.Image.FromFile(path1);
                    //生成缩略图
                    smallImage=FlagImage.GetThumbnailImage(130,100,callb,new System.IntPtr());
                    //保存加水印后的缩略图
                    smallImage.Save(Server.MapPath("upFile")+"\\small"+imageName);
                    //释放对象占用的资源
                    FlagImage.Dispose();
                    smallImage.Dispose();
                    //删除原图，删除加水印后的原图
                    if(File.Exists(ImgPath))
                    {
                        File.Delete(ImgPath);
                    }
                    if(File.Exists(path1))
                    {
                        File.Delete(path1);
                    }
                    //显示缩略图
                    showSmallPic.ImageUrl = "upFile/"+"small"+imageName;
                    Response.Write("上传成功!");
                }
                else
                {
                    this.Label1.Text="对不起！请您选择jpg或者gif格式的图片！";
                    return;
                }
            }
            else
            {
                this.Label1.Text="请选择图片！";
                return;
            }
        
        }
    }
}
posted on 2007-03-21 16:16  海风吹呀吹  阅读(2156)  评论(2)  编辑  收藏  举报