如下的内容段是关于C# 通过ASHX保存上传的图片并制作高质量的缩略图的内容，应该能对小伙伴也有帮助。

<%@ WebHandler Language="C#" Class="UploadFile" Debug="true" %>using System;using System.Web;public class UploadFile : IHttpHandler{ public void Proce***equest(HttpContext context) { context.Response.ContentType = "text/plain"; HttpPostedFile f1 = context.Request.Files["f1"]; String fileExt = System.IO.Path.GetExtension(f1.FileName); System.Drawing.Image image = System.Drawing.Image.FromStream(f1.InputStream); int newWidth = 300, newHeight = 200; if ((decimal)image.Width / image.Height > (decimal)newWidth / newHeight) { } else if ((decimal)image.Width / image.Height < (decimal)newWidth / newHeight) { } System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(newWidth, newHeight); System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bmp); g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality; g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; System.Drawing.Rectangle rectDestination = new System.Drawing.Rectangle(0, 0, newWidth, newHeight); g.DrawImage(image, rectDestination, 0, 0, image.Width, image.Height, System.Drawing.GraphicsUnit.Pixel); bmp.Save(context.Server.MapPath("~/") + DateTime.Now.ToString("yyyyMMddHHmmss") + fileExt); bmp.Dispose(); image.Dispose(); context.Response.Write("OK"); } public bool IsReusable { get { return false; } }}

上传表单

<form id="form1" action="UploadFile.ashx" method="post" enctype="multipart/form-data"><input type="file" name="f1" /><input type="submit" /></form>