ASP.NET2.0打通文件图片处理任督二脉 (2)

    // 方法1，按大小
    public bool ReducedImage(int Width, int Height, string targetFilePath)
    {
        try
        {
            Image ReducedImage;
            Image.GetThumbnailImageAbort callb = new Image.GetThumbnailImageAbort(ThumbnailCallback);
            ReducedImage = ResourceImage.GetThumbnailImage(Width, Height, callb, IntPtr.Zero);
            ReducedImage.Save(@targetFilePath, ImageFormat.Jpeg);
            ReducedImage.Dispose();
            return true;
        }
        catch (Exception e)
        {
            ErrorMessage = e.Message;
            return false;
        }
    }

    // 方法2，按百分比  缩小60% Percent为0.6 targetFilePath为目标路径
    public bool ReducedImage(double Percent, string targetFilePath)
    {
        try
        {
            Image ReducedImage;
            Image.GetThumbnailImageAbort callb = new Image.GetThumbnailImageAbort(ThumbnailCallback);
            ImageWidth = Convert.ToInt32(ResourceImage.Width * Percent);
            ImageHeight = (ResourceImage.Height)*ImageWidth/ ResourceImage.Width;//等比例缩放
            ReducedImage = ResourceImage.GetThumbnailImage(ImageWidth, ImageHeight, callb, IntPtr.Zero);
            ReducedImage.Save(@targetFilePath, ImageFormat.Jpeg);
            ReducedImage.Dispose();
            return true;
        }
        catch (Exception e)
        {
            ErrorMessage = e.Message;
            return false;
        }
    }

}

后台代码：
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;
public partial class _Default : System.Web.UI.Page
{

    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void bt_upload_Click(object sender, EventArgs e)
    {
        try
        {
            if (FileUpload1.PostedFile.FileName == "")
            {
                this.lb_info.Text = "请选择文件！";
            }
            else
            {
                string filepath = FileUpload1.PostedFile.FileName;
                string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
                string serverpath1 = Server.MapPath("images/") + filename;
                string serverpath2 = Server.MapPath("images/") + System.DateTime.Now.ToString("yyy-MM-dd-hh-mm-ss") + Session.SessionID + filename;
                FileUpload1.PostedFile.SaveAs(serverpath1);
                ImageThumbnail img = new ImageThumbnail(filepath);
                img.ReducedImage(0.4, serverpath2);//0.4表示缩小40%
                this.lb_info.Text = "上传成功！";
            }
        }
        catch (Exception error)
        {
            this.lb_info.Text = "上传发生错误！原因：" + error.ToString();
        }
    }

}

8.上传图片加水印(文字水印，图片水印，文字+图片水印)

效果图：
原图

水印

给图片加水印以后（注意右上角+正下方）