时间:2021-07-01 10:21:17 帮助过:22人阅读
前言
本文主要给大家介绍的是asp .net实现给图片添加图片水印的方法,注意是图片水印,需要的朋友们可以参考学习,下面话不多说来看看详细的介绍吧。
方法如下
首先写好一个写入图片水印的类,先创建一个ImageWriter类库 (该类中有包含枚举类型和方法)
- using System;
- using System.Collections.Generic;
- using System.Linq;
- using System.Text;
- using System.IO;
- using System.Collections;
- using System.Drawing;
- using System.Drawing.Drawing2D;
- using System.Drawing.Imaging;
- namespace ImageWriter
- {
- /// <summary>
- /// 图片处理类
- /// </summary>
- public class ImageManager
- {
- #region 变量声明开始
- /// <summary>
- /// 枚举: 水印位置
- /// </summary>
- public enum WatermarkPosition
- {
- /// <summary>
- /// 左上
- /// </summary>
- LeftTop,
- /// <summary>
- /// 左中
- /// </summary>
- Left,
- /// <summary>
- /// 左下
- /// </summary>
- LeftBottom,
- /// <summary>
- /// 正上
- /// </summary>
- Top,
- /// <summary>
- /// 正中
- /// </summary>
- Center,
- /// <summary>
- /// 正下
- /// </summary>
- Bottom,
- /// <summary>
- /// 右上
- /// </summary>
- RightTop,
- /// <summary>
- /// 右中
- /// </summary>
- RightCenter,
- /// <summary>
- /// 右下
- /// </summary>
- RigthBottom
- }
- #endregion 变量声明结束
- #region 构造函数开始
- /// <summary>
- /// 构造函数: 默认
- /// </summary>
- public ImageManager()
- { }
- #endregion 构造函数结束
- #region 私有函数开始
- /// <summary>
- /// 获取: 图片去扩展名(包含完整路径及其文件名)小写字符串
- /// </summary>
- /// <param name="path">图片路径(包含完整路径,文件名及其扩展名): string</param>
- /// <returns>返回: 图片去扩展名(包含完整路径及其文件名)小写字符串: string</returns>
- private string GetFileName(string path)
- {
- return path.Remove(path.LastIndexOf('.')).ToLower();
- }
- /// <summary>
- /// 获取: 图片以'.'开头的小写字符串扩展名
- /// </summary>
- /// <param name="path">图片路径(包含完整路径,文件名及其扩展名): string</param>
- /// <returns>返回: 图片以'.'开头的小写字符串扩展名: string</returns>
- private string GetExtension(string path)
- {
- return path.Remove(0, path.LastIndexOf('.')).ToLower();
- }
- /// <summary>
- /// 获取: 图片以 '.' 开头的小写字符串扩展名对应的 System.Drawing.Imaging.ImageFormat 对象
- /// </summary>
- /// <param name="format">以 '. '开头的小写字符串扩展名: string</param>
- /// <returns>返回: 图片以 '.' 开头的小写字符串扩展名对应的 System.Drawing.Imaging.ImageFormat 对象: System.Drawing.Imaging.ImageFormat</returns>
- private ImageFormat GetImageFormat(string format)
- {
- switch (format)
- {
- case ".bmp":
- return ImageFormat.Bmp;
- case ".emf":
- return ImageFormat.Emf;
- case ".exif":
- return ImageFormat.Exif;
- case ".gif":
- return ImageFormat.Gif;
- case ".ico":
- return ImageFormat.Icon;
- case ".png":
- return ImageFormat.Png;
- case ".tif":
- return ImageFormat.Tiff;
- case ".tiff":
- return ImageFormat.Tiff;
- case ".wmf":
- return ImageFormat.Wmf;
- default:
- return ImageFormat.Jpeg;
- }
- }
- /// <summary>
- /// 获取: 枚举 Uinatlex.ToolBox.ImageManager.WatermarkPosition 对应的 System.Drawing.Rectangle 对象
- /// </summary>
- /// <param name="positon">枚举 Uinatlex.ToolBox.ImageManager.WatermarkPosition: Uinatlex.ToolBox.ImageManager.WatermarkPosition</param>
- /// <param name="X">原图宽度: int</param>
- /// <param name="Y">原图高度: int</param>
- /// <param name="x">水印宽度: int</param>
- /// <param name="y">水印高度: int</param>
- /// <param name="i">边距: int</param>
- /// <returns>返回: 枚举 Uinatlex.ToolBox.ImageManager.WatermarkPosition 对应的 System.Drawing.Rectangle 对象: System.Drawing.Rectangle</returns>
- private Rectangle GetWatermarkRectangle(WatermarkPosition positon, int X, int Y, int x, int y, int i)
- {
- switch (positon)
- {
- case WatermarkPosition.LeftTop:
- return new Rectangle(i, i, x, y);
- case WatermarkPosition.Left:
- return new Rectangle(i, (Y - y) / 2, x, y);
- case WatermarkPosition.LeftBottom:
- return new Rectangle(i, Y - y - i, x, y);
- case WatermarkPosition.Top:
- return new Rectangle((X - x) / 2, i, x, y);
- case WatermarkPosition.Center:
- return new Rectangle((X - x) / 2, (Y - y) / 2, x, y);
- case WatermarkPosition.Bottom:
- return new Rectangle((X - x) / 2, Y - y - i, x, y);
- case WatermarkPosition.RightTop:
- return new Rectangle(X - x - i, i, x, y);
- case WatermarkPosition.RightCenter:
- return new Rectangle(X - x - i, (Y - y) / 2, x, y);
- default:
- return new Rectangle(X - x - i, Y - y - i, x, y);
- }
- }
- #endregion 私有函数结束
- #region 文字生成开始
- #endregion 文字生成结束
- #region 设置透明度开始
- /// <summary>
- /// 设置: 图片 System.Drawing.Bitmap 对象透明度
- /// </summary>
- /// <param name="sBitmap">图片 System.Drawing.Bitmap 对象: System.Drawing.Bitmap</param>
- /// <param name="transparence">水印透明度(值越高透明度越低,范围在0.0f~1.0f之间): float</param>
- /// <returns>图片 System.Drawing.Bitmap: System.Drawing.Bitmap</returns>
- public Bitmap SetTransparence(Bitmap bm, float transparence)
- {
- if (transparence == 0.0f || transparence == 1.0f)
- throw new ArgumentException("透明度值只能在0.0f~1.0f之间");
- float[][] floatArray =
- {
- new float[] { 1.0f, 0.0f, 0.0f, 0.0f, 0.0f },
- new float[] { 0.0f, 1.0f, 0.0f, 0.0f, 0.0f },
- new float[] { 0.0f, 0.0f, 1.0f, 0.0f, 0.0f },
- new float[] { 0.0f, 0.0f, 0.0f, transparence, 0.0f },
- new float[] { 0.0f, 0.0f, 0.0f, 0.0f, 1.0f }
- };
- ImageAttributes imageAttributes = new ImageAttributes();
- imageAttributes.SetColorMatrix(new ColorMatrix(floatArray), ColorMatrixFlag.Default, ColorAdjustType.Bitmap);
- Bitmap bitmap = new Bitmap(bm.Width, bm.Height);
- Graphics graphics = Graphics.FromImage(bitmap);
- graphics.DrawImage(bm, new Rectangle(0, 0, bm.Width, bm.Height), 0, 0, bm.Width, bm.Height, GraphicsUnit.Pixel, imageAttributes);
- graphics.Dispose();
- imageAttributes.Dispose();
- bm.Dispose();
- return bitmap;
- }
- /// <summary>
- /// 设置: 图片 System.Drawing.Bitmap 对象透明度
- /// </summary>
- /// <param name="readpath">图片路径(包含完整路径,文件名及其扩展名): string</param>
- /// <param name="transparence">水印透明度(值越高透明度越低,范围在0.0f~1.0f之间): float</param>
- /// <returns>图片 System.Drawing.Bitmap: System.Drawing.Bitmap</returns>
- public Bitmap SetTransparence(string readpath, float transparence)
- {
- return SetTransparence(new Bitmap(readpath), transparence);
- }
- #endregion 设置透明度结束
- #region 添加水印开始
- /// <summary>
- /// 生成: 原图绘制水印的 System.Drawing.Bitmap 对象
- /// </summary>
- /// <param name="sBitmap">原图 System.Drawing.Bitmap 对象: System.Drawing.Bitmap</param>
- /// <param name="wBitmap">水印 System.Drawing.Bitmap 对象: System.Drawing.Bitmap</param>
- /// <param name="position">枚举 Uinatlex.ToolBox.ImageManager.WatermarkPosition : Uinatlex.ToolBox.ImageManager.WatermarkPosition</param>
- /// <param name="margin">水印边距: int</param>
- /// <returns>返回: 原图绘制水印的 System.Drawing.Bitmap 对象 System.Drawing.Bitmap</returns>
- public Bitmap CreateWatermark(Bitmap sBitmap, Bitmap wBitmap, WatermarkPosition position, int margin)
- {
- Graphics graphics = Graphics.FromImage(sBitmap);
- graphics.DrawImage(wBitmap, GetWatermarkRectangle(position, sBitmap.Width, sBitmap.Height, wBitmap.Width, wBitmap.Height, margin));
- graphics.Dispose();
- wBitmap.Dispose();
- return sBitmap;
- }
- #endregion 添加水印结束
- #region 图片切割开始
- #endregion 图片切割结束
- #region 图片缩放开始
- #endregion 图片缩放结束
- #region 保存图片到文件开始
- #region 普通保存开始
- /// <summary>
- /// 保存: System.Drawing.Bitmap 对象到图片文件
- /// </summary>
- /// <param name="bitmap">System.Drawing.Bitmap 对象: System.Drawing.Bitmap</param>
- /// <param name="writepath">保存路径(包含完整路径,文件名及其扩展名): string</param>
- public void Save(Bitmap bitmap, string writepath)
- {
- try
- {
- bitmap.Save(writepath, GetImageFormat(GetExtension(writepath)));
- bitmap.Dispose();
- }
- catch
- {
- throw new ArgumentException("图片保存错误");
- }
- }
- /// <summary>
- /// 保存: 对象到图片文件
- /// </summary>
- /// <param name="readpath">原图路径(包含完整路径,文件名及其扩展名): string</param>
- /// <param name="writepath">保存路径(包含完整路径,文件名及其扩展名): string</param>
- public void Save(string readpath, string writepath)
- {
- if (string.Compare(readpath, writepath) == 0)
- throw new ArgumentException("源图片与目标图片地址相同");
- try
- {
- Save(new Bitmap(readpath), writepath);
- }
- catch
- {
- throw new ArgumentException("图片读取错误");
- }
- }
- #endregion 普通保存结束
- #region 文字绘图保存开始
- #endregion 文字绘图保存结束
- #region 透明度调整保存开始
- /// <summary>
- /// 保存: 设置透明度的对象到图片文件
- /// </summary>
- /// <param name="sBitmap">图片 System.Drawing.Bitmap 对象: System.Drawing.Bitmap</param>
- /// <param name="transparence">水印透明度(值越高透明度越低,范围在0.0f~1.0f之间): float</param>
- /// <param name="writepath">保存路径(包含完整路径,文件名及其扩展名): string</param>
- public void SaveTransparence(Bitmap bitmap, float transparence, string writepath)
- {
- Save(SetTransparence(bitmap, transparence), writepath);
- }
- /// <summary>
- /// 保存: 设置透明度的象到图片文件
- /// </summary>
- /// <param name="readpath">原图路径(包含完整路径,文件名及其扩展名): string</param>
- /// <param name="transparence">水印透明度(值越高透明度越低,范围在0.0f~1.0f之间): float</param>
- /// <param name="writepath">保存路径(包含完整路径,文件名及其扩展名): string</param>
- public void SaveTransparence(string readpath, float transparence, string writepath)
- {
- Save(SetTransparence(readpath, transparence), writepath);
- }
- #endregion 透明度调整保存结束
- #region 水印图片保存开始
- /// <summary>
- /// 保存: 绘制水印的对象到图片文件
- /// </summary>
- /// <param name="sBitmap">原图 System.Drawing.Bitmap 对象: System.Drawing.Bitmap</param>
- /// <param name="wBitmap">水印 System.Drawing.Bitmap 对象: System.Drawing.Bitmap</param>
- /// <param name="position">枚举 Uinatlex.ToolBox.ImageManager.WatermarkPosition : Uinatlex.ToolBox.ImageManager.WatermarkPosition</param>
- /// <param name="margin">水印边距: int</param>
- /// <param name="writepath">保存路径(包含完整路径,文件名及其扩展名): string</param>
- public void SaveWatermark(Bitmap sBitmap, Bitmap wBitmap, WatermarkPosition position, int margin, string writepath)
- {
- Save(CreateWatermark(sBitmap, wBitmap, position, margin), writepath);
- }
- /// <summary>
- /// 保存: 绘制水印的对象到图片文件
- /// </summary>
- /// <param name="readpath">图片路径(包含完整路径,文件名及其扩展名): string</param>
- /// <param name="watermarkpath">水印图片路径(包含完整路径,文件名及其扩展名): string</param>
- /// <param name="transparence">水印透明度(值越高透明度越低,范围在0.0f~1.0f之间): float</param>
- /// <param name="position">枚举 Uinatlex.ToolBox.ImageManager.WatermarkPosition : Uinatlex.ToolBox.ImageManager.WatermarkPosition</param>
- /// <param name="margin">水印边距: int</param>
- /// <param name="writepath">保存路径(包含完整路径,文件名及其扩展名): string</param>
- public void SaveWatermark(string readpath, string watermarkpath, float transparence, WatermarkPosition position, int margin, string writepath)
- {
- if (string.Compare(readpath, writepath) == 0)
- throw new ArgumentException("源图片与目标图片地址相同");
- if (transparence == 0.0f)
- Save(readpath, writepath);
- else if (transparence == 1.0f)
- SaveWatermark(new Bitmap(readpath), new Bitmap(watermarkpath), position, margin, writepath);
- else
- SaveWatermark(new Bitmap(readpath), SetTransparence(watermarkpath, transparence), position, margin, writepath);
- }
- #endregion 水印图片保存结束
- #region 图片切割保存开始
- #endregion 图片切割保存结束
- #region 图片缩放保存开始
- #endregion 图片缩放保存开始
- #endregion 保存图片到文件结束
- }
- }
- /*
- 调用很简单 im.SaveWatermark(原图地址, 水印地址, 透明度, 水印位置, 边距,保存位置);
- Uinatlex.ToolBox.ImageManager im = new Uinatlex.ToolBox.ImageManager();
- im.SaveWatermark(Server.MapPath("/原图.jpg"), Server.MapPath("/水印.jpg"), 0.5f, Uinatlex.ToolBox.ImageManager.WatermarkPosition.RigthBottom, 10, Server.MapPath("/原图.jpg"));
- */
在客户端页面中调用上面这个类
- protected void Page_Load(object sender, EventArgs e)
- {
- string newfileName = Server.MapPath("img/") + DateTime.Now.Millisecond + "" + DateTime.Now.Second + ".jpg";
- ImageManager im = new ImageManager();
- //调用很简单 im.SaveWatermark(原图地址, 水印地址, 透明度, 水印位置, 边距,保存到的位置);
- im.SaveWatermark(Server.MapPath("img/Chrysanthemum.jpg"), Server.MapPath("img/woshi.jpg"), 0.9f, ImageManager.WatermarkPosition.RigthBottom, 10, newfileName);
- }
总结
好了,以上就是这篇文章的全部内容了,希望本文的内容对大家的学习或者工作能带来一定的帮助,如果有疑问大家可以留言交流,谢谢大家对脚本之家的支持。