asp.net 生成缩略图、为图片添加文字水印、图片水印等功能

最近挺嫌的荒，不知道写点什么好，就在网上找了个类似的例子，自己重新写了一遍,稍微改了一下。希望对大家有用

实现了生成缩略图、为图片添加文字水印、图片水印等功能

源代码打包下载:http://files.cnblogs.com/ywqu/ThumPicture.rar

using System;
using System.Data;
using System.Configuration;
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;

/// <summary>
/// 生成缩略图、为图片添加文字水印、图片水印的类
/// </summary>
public class ThumNail
{
public ThumNail()
{
//
// TODO: Add constructor logic here
//
}
/// <summary>
/// 生成缩略图
/// </summary>
/// <param name="orginalImagePat">原图片地址</param>
/// <param name="thumNailPath">缩略图地址</param>
/// <param name="width">缩略图宽度</param>
/// <param name="height">缩略图高度</param>
/// <param name="model">生成缩略的模式</param>
public static void MakeThumNail(string originalImagePath,string thumNailPath,int width,int height,string model)
{
System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath);

int thumWidth = width; //缩略图的宽度
int thumHeight = height; //缩略图的高度

int x = 0;
int y = 0;

int originalWidth = originalImage.Width; //原始图片的宽度
int originalHeight = originalImage.Height; //原始图片的高度

switch (model)
{
case "HW": //指定高宽缩放,可能变形
break;
case "W": //指定宽度,高度按照比例缩放
thumHeight = originalImage.Height * width / originalImage.Width;
break;
case "H": //指定高度,宽度按照等比例缩放
thumWidth = originalImage.Width * height / originalImage.Height;
break;
case "Cut":
if ((double)originalImage.Width / (double)originalImage.Height > (double)thumWidth / (double)thumHeight)
{
originalHeight = originalImage.Height;
originalWidth = originalImage.Height * thumWidth / thumHeight;
y = 0;
x = (originalImage.Width - originalWidth) / 2;
}
else
{
originalWidth = originalImage.Width;
originalHeight = originalWidth * height / thumWidth;
x = 0;
y = (originalImage.Height - originalHeight) / 2;
}
break;
default:
break;
}

//新建一个bmp图片
System.Drawing.Image bitmap = new System.Drawing.Bitmap(thumWidth,thumHeight);

//新建一个画板
System.Drawing.Graphics graphic=System.Drawing.Graphics.FromImage(bitmap);

//设置高质量查值法
graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;

//设置高质量，低速度呈现平滑程度
graphic.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

//清空画布并以透明背景色填充
graphic.Clear(System.Drawing.Color.Transparent);

//在指定位置并且按指定大小绘制原图片的指定部分
graphic.DrawImage(originalImage, new System.Drawing.Rectangle(0, 0, thumWidth, thumHeight), new System.Drawing.Rectangle(x, y, originalWidth, originalHeight), System.Drawing.GraphicsUnit.Pixel);

try
{
bitmap.Save(thumNailPath, System.Drawing.Imaging.ImageFormat.Jpeg);
}
catch (Exception ex)
{

throw ex;
}
finally
{
originalImage.Dispose();
bitmap.Dispose();
graphic.Dispose();
}

}

/// <summary>
/// 在图片上添加文字水印
/// </summary>
/// <param name="path">要添加水印的图片路径</param>
/// <param name="syPath">生成的水印图片存放的位置</param>
public static void AddWaterWord(string path,string syPath)
{
string syWord = "http://www.hello36.cn";
System.Drawing.Image image = System.Drawing.Image.FromFile(path);

//新建一个画板
System.Drawing.Graphics graphic = System.Drawing.Graphics.FromImage(image);
graphic.DrawImage(image,0,0,image.Width,image.Height);

//设置字体
System.Drawing.Font f = new System.Drawing.Font("Verdana",60);

//设置字体颜色
System.Drawing.Brush b = new System.Drawing.SolidBrush(System.Drawing.Color.Green);

graphic.DrawString(syWord, f, b, 35, 35);
graphic.Dispose();

//保存文字水印图片
image.Save(syPath);
image.Dispose();

}

/// <summary>
/// 在图片上添加图片水印
/// </summary>
/// <param name="path">原服务器上的图片路径</param>
/// <param name="syPicPath">水印图片的路径</param>
/// <param name="waterPicPath">生成的水印图片存放路径</param>
public static void AddWaterPic(string path, string syPicPath, string waterPicPath)
{
System.Drawing.Image image = System.Drawing.Image.FromFile(path);
System.Drawing.Image waterImage = System.Drawing.Image.FromFile(syPicPath);
System.Drawing.Graphics graphic = System.Drawing.Graphics.FromImage(image);
graphic.DrawImage(waterImage,new System.Drawing.Rectangle(image.Width-waterImage.Width,image.Height-waterImage.Height,waterImage.Width,waterImage.Height),0,0,waterImage.Width,waterImage.Height,System.Drawing.GraphicsUnit.Pixel);
graphic.Dispose();

image.Save(waterPicPath);
image.Dispose();
}

}
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