1using System;
2using System.Data;
3using System.Configuration;
4using System.Web;
5using System.Web.Security;
6using System.Web.UI;
7using System.Web.UI.WebControls;
8using System.Web.UI.WebControls.WebParts;
9using System.Web.UI.HtmlControls;
10using System.Drawing;
11namespace WebHelper
12{
13
14 /**//// <summary>
15 /// ImageHelper 的摘要说明
16 /// </summary>
17 public class ImageHelper
18 {
19 public ImageHelper()
20 {
21 //
22 // TODO: 在此处添加构造函数逻辑
23 //
24 }
25 Image水印#region Image水印
26 /**//// <summary>
27 /// 写入图像水印
28 /// </summary>
29 /// <param name="str">水印字符串</param>
30 /// <param name="filePath">原图片位置</param>
31 /// <param name="savePath">水印加入后的位置</param>
32 /// <returns></returns>
33 public string CreateBackImage(System.Web.UI.Page pageCurrent, string str, string filePath, string savePath, int x, int y)
34 {
35 System.Drawing.Image img = System.Drawing.Image.FromFile(pageCurrent.MapPath(filePath));
36 //创建图片
37 Graphics graphics = Graphics.FromImage(img);
38 //指定要绘制的面积
39 graphics.DrawImage(img, 0, 0, img.Width, img.Height);
40 //定义字段和画笔
41 Font font = new Font("黑体", 16);
42 Brush brush = new SolidBrush(Color.Yellow);
43 graphics.DrawString(str, font, brush, x, y);
44 //保存并输出图片
45 img.Save(pageCurrent.MapPath(savePath), System.Drawing.Imaging.ImageFormat.Jpeg);
46 return savePath;
47
48 }
49 #endregion
50 Image自动缩小#region Image自动缩小
51 /**//// <summary>
52 /// 缩小图片到指定的大小
53 /// </summary>
54 /// <param name="strOldPic">
55 /// 原图片的位置
56 /// </param>
57 /// <param name="strNewPic">
58 /// 缩小后的图片位置
59 /// </param>
60 /// <param name="intWidth">
61 /// 宽度
62 /// </param>
63 /// <param name="intHeight">
64 /// 高度
65 /// </param>
66 public void SmallPic(string strOldPic, string strNewPic, int intWidth, int intHeight)
67 {
68
69 System.Drawing.Bitmap objPic, objNewPic;
70 try
71 {
72 objPic = new System.Drawing.Bitmap(strOldPic);
73 objNewPic = new System.Drawing.Bitmap(objPic, intWidth, intHeight);
74 objNewPic.Save(strNewPic);
75
76 }
77 catch (Exception exp) { throw exp; }
78 finally
79 {
80 objPic = null;
81 objNewPic = null;
82 }
83 }
84
85 public void SmallPic(string strOldPic, string strNewPic, int intWidth)
86 {
87
88 System.Drawing.Bitmap objPic, objNewPic;
89 try
90 {
91 objPic = new System.Drawing.Bitmap(strOldPic);
92 int intHeight = Convert.ToInt32(((intWidth * 1.0) / (objPic.Width * 1.0)) * objPic.Height);
93 objNewPic = new System.Drawing.Bitmap(objPic, intWidth, intHeight);
94 objNewPic.Save(strNewPic, objPic.RawFormat);
95
96 }
97 catch (Exception exp) { throw exp; }
98 finally
99 {
100 objPic = null;
101 objNewPic = null;
102 }
103 }
104
105 //public void SmallPic(string strOldPic, string strNewPic, int intHeight)
106 //{
107
108 // System.Drawing.Bitmap objPic, objNewPic;
109 // try
110 // {
111 // objPic = new System.Drawing.Bitmap(strOldPic);
112 // int intWidth = Convert.ToInt32(((intHeight * 1.0) / objPic.Height) * objPic.Width);
113 // objNewPic = new System.Drawing.Bitmap(objPic, intWidth, intHeight);
114 // objNewPic.Save(strNewPic, objPic.RawFormat);
115
116 // }
117 // catch (Exception exp) { throw exp; }
118 // finally
119 // {
120 // objPic = null;
121 // objNewPic = null;
122 // }
123 //}
124 #endregion
125
126 }
127}
http://www.cnblogs.com/chu888chu888/archive/2007/01/09/615803.html
