asp.net 上传图片生成缩略图

 

/**/ /// <summary> /// 在图片上增加文字水印 /// </summary> /// <param name="Path">原服务器图片路径</param> /// <param name="Path_sy">生成的带文字水印的图片路径</param> protected void AddWater(string Path, string Path_sy) { string addText = "51aspx.com"; System.Drawing.Image image = System.Drawing.Image.FromFile(Path); System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(image); g.DrawImage(image, 0, 0, image.Width, image.Height); System.Drawing.Font f = new System.Drawing.Font("Verdana", 60); System.Drawing.Brush b = new System.Drawing.SolidBrush(System.Drawing.Color.Green); g.DrawString(addText, f, b, 35, 35); g.Dispose(); image.Save(Path_sy); image.Dispose(); } 

/**/ /// <summary> /// 在图片上生成图片水印 /// </summary> /// <param name="Path">原服务器图片路径</param> /// <param name="Path_syp">生成的带图片水印的图片路径</param> /// <param name="Path_sypf">水印图片路径</param> protected void AddWaterPic(string Path, string Path_syp, string Path_sypf) { System.Drawing.Image image = System.Drawing.Image.FromFile(Path); System.Drawing.Image copyImage = System.Drawing.Image.FromFile(Path_sypf); System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(image); g.DrawImage(copyImage, new System.Drawing.Rectangle(image.Width - copyImage.Width, image.Height - copyImage.Height, copyImage.Width, copyImage.Height), 0, 0, copyImage.Width, copyImage.Height, System.Drawing.GraphicsUnit.Pixel); g.Dispose(); image.Save(Path_syp); image.Dispose(); } 

/// <summary> /// 给图片上水印 /// </summary> /// <mce:script type="text/javascript" src="http://hi.images.csdn.net/js/blog/tiny_mce/themes/advanced/langs/zh.js" mce_src="http://hi.images.csdn.net/js/blog/tiny_mce/themes/advanced/langs/zh.js"></mce:script><mce:script type="text/javascript" src="http://hi.images.csdn.net/js/blog/tiny_mce/plugins/syntaxhl/langs/zh.js" mce_src="http://hi.images.csdn.net/js/blog/tiny_mce/plugins/syntaxhl/langs/zh.js"></mce:script>amp;lt;param name="filePath">原图片地址</param> /// <param name="waterFile">水印图片地址</param> public void MarkWater(string filePaths, string waterFile) { //GIF不水印 int i = filePaths.LastIndexOf("."); string ex = filePaths.Substring(i, filePaths.Length - i); if (string.Compare(ex, ".gif", true) == 0) { return; } string ModifyImagePath = filePaths;// FilePath + filePaths;//修改的图像路径 int lucencyPercent = 25; System.Drawing.Image modifyImage = null; System.Drawing.Image drawedImage = null; Graphics g = null; try { //建立图形对象 modifyImage = System.Drawing.Image.FromFile(ModifyImagePath, true); // drawedImage = System.Drawing.Image.FromFile(FilePath + waterFile, true); drawedImage = System.Drawing.Image.FromFile(waterFile, true); g = Graphics.FromImage(modifyImage); //获取要绘制图形坐标 int x = modifyImage.Width - drawedImage.Width; int y = modifyImage.Height - drawedImage.Height; //设置颜色矩阵 float[][] matrixItems ={ new float[] {1, 0, 0, 0, 0}, new float[] {0, 1, 0, 0, 0}, new float[] {0, 0, 1, 0, 0}, new float[] {0, 0, 0, (float)lucencyPercent/1f, 0}, new float[] {0, 0, 0, 0, 1}}; ColorMatrix colorMatrix = new ColorMatrix(matrixItems); ImageAttributes imgAttr = new ImageAttributes(); imgAttr.SetColorMatrix(colorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap); //绘制阴影图像 g.DrawImage(drawedImage, new Rectangle(x, y, drawedImage.Width, drawedImage.Height), 0, 0, drawedImage.Width, drawedImage.Height, GraphicsUnit.Pixel, imgAttr); //保存文件 string[] allowImageType ={ ".jpg", ".gif", ".png", ".bmp", ".tiff", ".wmf", ".ico" }; FileInfo fi = new FileInfo(ModifyImagePath); ImageFormat imageType = ImageFormat.Gif; switch (fi.Extension.ToLower()) { case ".jpg": imageType = ImageFormat.Jpeg; break; case ".gif": imageType = ImageFormat.Gif; break; case ".png": imageType = ImageFormat.Png; break; case ".bmp": imageType = ImageFormat.Bmp; break; case ".tif": imageType = ImageFormat.Tiff; break; case ".wmf": imageType = ImageFormat.Wmf; break; case ".ico": imageType = ImageFormat.Icon; break; default: break; } MemoryStream ms = new MemoryStream(); modifyImage.Save(ms, imageType); byte[] imgData = ms.ToArray(); modifyImage.Dispose(); drawedImage.Dispose(); g.Dispose(); FileStream fs = null; File.Delete(ModifyImagePath); fs = new FileStream(ModifyImagePath, FileMode.Create, FileAccess.Write); if (fs != null) { fs.Write(imgData, 0, imgData.Length); fs.Close(); } } finally { try { drawedImage.Dispose(); modifyImage.Dispose(); g.Dispose(); } catch { ;} } }  

protected void Button1_Click(object sender, EventArgs e) { string tt=string.Empty; if (FileUpload1.HasFile) { string fileContentType = FileUpload1.PostedFile.ContentType; if (fileContentType == "image/bmp" || fileContentType == "image/gif" || fileContentType == "image/pjpeg") { string name = FileUpload1.PostedFile.FileName; // 客户端文件路径 FileInfo file = new FileInfo(name); string fileName = file.Name; // 文件名称 tt=fileName; string fileName_s = "s_" + file.Name; // 缩略图文件名称 string fileName_sy = "sy_" + file.Name; // 水印图文件名称（文字） string fileName_syp = "syp_" + file.Name; // 水印图文件名称（图片） string webFilePath = Server.MapPath("file/" + fileName); // 服务器端文件路径 string webFilePath_s = Server.MapPath("file/" + fileName_s);　　// 服务器端缩略图路径 string webFilePath_sy = Server.MapPath("file/" + fileName_sy);　// 服务器端带水印图路径(文字) string webFilePath_syp = Server.MapPath("file/" + fileName_syp);　// 服务器端带水印图路径(图片) string webFilePath_sypf = Server.MapPath("file/shuiyin.jpg");　// 服务器端水印图路径(图片) if (!File.Exists(webFilePath)) { try { FileUpload1.SaveAs(webFilePath); // 使用 SaveAs 方法保存文件 AddWater(webFilePath, webFilePath_sy); AddWaterPic(webFilePath, webFilePath_syp, webFilePath_sypf); MakeThumbnail(webFilePath, webFilePath_s, 130, 130, "Cut"); // 生成缩略图方法 MarkWater(webFilePath, webFilePath_sy); Label1.Text = "提示：文件“" + fileName + "”成功上传，并生成“" + fileName_s + "”缩略图，文件类型为：" + FileUpload1.PostedFile.ContentType + "，文件大小为：" + FileUpload1.PostedFile.ContentLength + "B"; this.Image1.ImageUrl = "file/" + fileName_s; } catch (Exception ex) { Label1.Text = "提示：文件上传失败，失败原因：" + ex.Message; } } else { Label1.Text = "提示：文件已经存在，请重命名后上传"; } } else { Label1.Text = "提示：文件类型不符"; } } }