原文地址:http://www.qqroom.com/Member/Blog/ItemView.aspx?BlogItemID=397&UserName=Jerry
今天突然看到这篇帖子,代码如下
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;
namespace LabWeb
{
public class XuDrawImage
{
/// <summary>
/// 生成缩略图
/// </summary>
/// <param name="originalImagePath">源图路径（物理路径）</param>
/// <param name="thumbnailPath">缩略图路径（物理路径）</param>
/// <param name="width">缩略图宽度</param>
/// <param name="height">缩略图高度</param>
/// <param name="mode">生成缩略图的方式</param>
public static void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)
{
Image originalImage = Image.FromFile(originalImagePath);
int towidth = width;
int toheight = height;
int x = 0;
int y = 0;
int ow = originalImage.Width;
int oh = originalImage.Height;
switch (mode)
{
case "HW"://指定高宽缩放（可能变形）
break;
case "W"://指定宽，高按比例
toheight = originalImage.Height * width / originalImage.Width;
break;
case "H"://指定高，宽按比例
towidth = originalImage.Width * height / originalImage.Height;
break;
case "Cut"://指定高宽裁减（不变形）
if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight)
{
oh = originalImage.Height;
ow = originalImage.Height * towidth / toheight;
y = 0;
x = (originalImage.Width - ow) / 2;
}
else
{
ow = originalImage.Width;
oh = originalImage.Width * height / towidth;
x = 0;
y = (originalImage.Height - oh) / 2;
}
break;
default:
break;
}
//新建一个bmp图片
Image bitmap = new System.Drawing.Bitmap(towidth, toheight);
//新建一个画板
Graphics g = System.Drawing.Graphics.FromImage(bitmap);
//设置双三次的高质量插值法
g.InterpolationMode = InterpolationMode.HighQualityBicubic;
//设置高质量,低速度呈现平滑程度
g.SmoothingMode = SmoothingMode.HighQuality;
//清空画布并以透明背景色填充
g.Clear(Color.Transparent);
//在指定位置并且按指定大小绘制原图片的指定部分
g.DrawImage(originalImage, new Rectangle(0, 0, towidth, toheight),
new Rectangle(x, y, ow, oh),
GraphicsUnit.Pixel);
try
{
//以jpg格式保存缩略图
bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg);
}
catch (System.Exception e)
{
throw e;
}
finally
{
originalImage.Dispose();
bitmap.Dispose();
g.Dispose();
}
}
}
}
我在页面上放了一个Input(file),一个按钮Button1,以及一个Image<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="XuDrawImageTest.aspx.cs" Inherits="LabWeb.XuDrawImageTest" EnableViewState="true" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>无标题页</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<input id="UpFile" runat="server" style="width: 400px" type="file" />
<asp:DropDownList ID="DropDownList1" runat="server">
<asp:ListItem>WH</asp:ListItem>
<asp:ListItem>W</asp:ListItem>
<asp:ListItem>H</asp:ListItem>
<asp:ListItem>Cut</asp:ListItem>
</asp:DropDownList>
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="上传图片!" />
<asp:Image ID="Image1" runat="server" /></div>
</form>
</body>
</html>
后台代码:protected void Button1_Click(object sender, EventArgs e)
{
if (this.UpFile.PostedFile.FileName.Trim() != "")
{
//取得上传文件的总路径
string imagePath = this.UpFile.PostedFile.FileName;
//取出图片的类型
string imageType = Path.GetExtension(imagePath).ToUpper();
//取得图片名称
string imageName = Path.GetFileName(imagePath).ToString();
imageName = System.DateTime.Now.ToString("yyyyMMddhhmmss") + imageType;
Response.Write(imagePath+"<br>"+imageType+"<br>"+imageName);
//判断上传图片类型
if (imageType == ".JPG" || imageType == ".BMP" || imageType == ".JPEG" || imageType == ".GIF")
{
//保存原图
string imageSavePath = Server.MapPath("/ProductPicFile" + "\\" + imageName);
this.UpFile.PostedFile.SaveAs(imageSavePath);
//生成第一幅缩略图
string drawMode = this.DropDownList1.SelectedValue.ToString();
string drawImageName= "S_" + DateTime.Now.ToString("yyyyMMddhhmmss")+".JPG";
string drawImageSavePath = Server.MapPath("/ProductPicFile"+"\\" +drawImageName);
LabWeb.XuDrawImage.MakeThumbnail(imageSavePath, drawImageSavePath, 100, 50, drawMode);
//定义image类的对象
System.Drawing.Image image, shuiyinImg;
//为上传的图片建立引用
image = System.Drawing.Image.FromFile(drawImageSavePath);
/*************加水印开始*********************************************/
shuiyinImg = System.Drawing.Image.FromFile(Server.MapPath("/Images/FlagImg/") + "Flag200_100.png");
Graphics g = Graphics.FromImage(image);
////设置双三次的高质量插值法
//g.InterpolationMode = InterpolationMode.HighQualityBicubic;
////设置高质量,低速度呈现平滑程度
//g.SmoothingMode = SmoothingMode.HighQuality;
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 drawFlagPath = Server.MapPath("/ProductPicFile" +"\\ff_"+ drawImageName);
image.Save(drawFlagPath);
image.Dispose();
/************加水印的过程结束*********************************************/
//删除原图
if (File.Exists(imageSavePath))
{
File.Delete(imageSavePath);
}
this.Image1.ImageUrl = drawFlagPath;
}
}
今天突然看到这篇帖子,代码如下
using System;using System.Drawing;using System.Drawing.Imaging;using System.Drawing.Drawing2D;namespace LabWeb{
public class XuDrawImage {
/// <summary> /// 生成缩略图 /// </summary> /// <param name="originalImagePath">源图路径（物理路径）</param> /// <param name="thumbnailPath">缩略图路径（物理路径）</param> /// <param name="width">缩略图宽度</param> /// <param name="height">缩略图高度</param> /// <param name="mode">生成缩略图的方式</param> public static void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode) { Image originalImage = Image.FromFile(originalImagePath); int towidth = width; int toheight = height; int x = 0; int y = 0; int ow = originalImage.Width; int oh = originalImage.Height; switch (mode) { case "HW"://指定高宽缩放（可能变形） break; case "W"://指定宽，高按比例 toheight = originalImage.Height * width / originalImage.Width; break; case "H"://指定高，宽按比例 towidth = originalImage.Width * height / originalImage.Height; break; case "Cut"://指定高宽裁减（不变形） if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight) { oh = originalImage.Height; ow = originalImage.Height * towidth / toheight; y = 0; x = (originalImage.Width - ow) / 2; } else { ow = originalImage.Width; oh = originalImage.Width * height / towidth; x = 0; y = (originalImage.Height - oh) / 2; } break; default: break; } //新建一个bmp图片 Image bitmap = new System.Drawing.Bitmap(towidth, toheight); //新建一个画板 Graphics g = System.Drawing.Graphics.FromImage(bitmap); //设置双三次的高质量插值法 g.InterpolationMode = InterpolationMode.HighQualityBicubic; //设置高质量,低速度呈现平滑程度 g.SmoothingMode = SmoothingMode.HighQuality; //清空画布并以透明背景色填充 g.Clear(Color.Transparent); //在指定位置并且按指定大小绘制原图片的指定部分 g.DrawImage(originalImage, new Rectangle(0, 0, towidth, toheight), new Rectangle(x, y, ow, oh), GraphicsUnit.Pixel); try { //以jpg格式保存缩略图 bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg); } catch (System.Exception e) { throw e; } finally { originalImage.Dispose(); bitmap.Dispose(); g.Dispose(); } } }}我在页面上放了一个Input(file),一个按钮Button1,以及一个Image
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="XuDrawImageTest.aspx.cs" Inherits="LabWeb.XuDrawImageTest" EnableViewState="true" %><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml" ><head runat="server"> <title>无标题页</title></head><body> <form id="form1" runat="server"> <div> <input id="UpFile" runat="server" style="width: 400px" type="file" /> <asp:DropDownList ID="DropDownList1" runat="server"> <asp:ListItem>WH</asp:ListItem> <asp:ListItem>W</asp:ListItem> <asp:ListItem>H</asp:ListItem> <asp:ListItem>Cut</asp:ListItem> </asp:DropDownList> <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="上传图片!" /> <asp:Image ID="Image1" runat="server" /></div> </form></body></html>后台代码:
protected void Button1_Click(object sender, EventArgs e) { if (this.UpFile.PostedFile.FileName.Trim() != "") { //取得上传文件的总路径 string imagePath = this.UpFile.PostedFile.FileName; //取出图片的类型 string imageType = Path.GetExtension(imagePath).ToUpper(); //取得图片名称 string imageName = Path.GetFileName(imagePath).ToString(); imageName = System.DateTime.Now.ToString("yyyyMMddhhmmss") + imageType; Response.Write(imagePath+"<br>"+imageType+"<br>"+imageName); //判断上传图片类型 if (imageType == ".JPG" || imageType == ".BMP" || imageType == ".JPEG" || imageType == ".GIF") { //保存原图 string imageSavePath = Server.MapPath("/ProductPicFile" + "\\" + imageName); this.UpFile.PostedFile.SaveAs(imageSavePath); //生成第一幅缩略图 string drawMode = this.DropDownList1.SelectedValue.ToString(); string drawImageName= "S_" + DateTime.Now.ToString("yyyyMMddhhmmss")+".JPG"; string drawImageSavePath = Server.MapPath("/ProductPicFile"+"\\" +drawImageName); LabWeb.XuDrawImage.MakeThumbnail(imageSavePath, drawImageSavePath, 100, 50, drawMode); //定义image类的对象 System.Drawing.Image image, shuiyinImg; //为上传的图片建立引用 image = System.Drawing.Image.FromFile(drawImageSavePath); /*************加水印开始*********************************************/ shuiyinImg = System.Drawing.Image.FromFile(Server.MapPath("/Images/FlagImg/") + "Flag200_100.png"); Graphics g = Graphics.FromImage(image); ////设置双三次的高质量插值法 //g.InterpolationMode = InterpolationMode.HighQualityBicubic; ////设置高质量,低速度呈现平滑程度 //g.SmoothingMode = SmoothingMode.HighQuality; 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 drawFlagPath = Server.MapPath("/ProductPicFile" +"\\ff_"+ drawImageName); image.Save(drawFlagPath); image.Dispose(); /************加水印的过程结束*********************************************/ //删除原图 if (File.Exists(imageSavePath)) { File.Delete(imageSavePath); } this.Image1.ImageUrl = drawFlagPath; } }
一个人的孤独，一个人的封闭，不如一起努力！
