日期:2014-05-17  浏览次数:20398 次

asp.net中在ashx文件里获得客户端上传的完整路径问题
C# code

HttpPostedFile fileValue = context.Request.Files["FileValue"];//FileValue是前台file控件的id

//如果我想获得客户选择文件的客户端的完整路径
 string test = fileValue.FileName;
//这样写我在ie浏览器中断点调试可以完全获得客户端的路径,我在ff或谷歌浏览器调试错误,只能获得文件名。不知道为什么。求解……



------解决方案--------------------
生成缩略图要客户端路径干嘛?需要的是服务器路径
另外,不要路径也能生成缩略图
不经保存,直接生成上传图片的等比例的高质量缩略图

HTML code

<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  protected void Button1_Click(object sender, EventArgs e)
  {
    String fileExt = System.IO.Path.GetExtension(FileUpload1.FileName);
    System.Drawing.Image image = System.Drawing.Image.FromStream(new System.IO.MemoryStream(FileUpload1.FileBytes));
    int newWidth = 300, newHeight = 200;
    if ((decimal)image.Width / image.Height > (decimal)newWidth / newHeight)
    {
      newHeight =Convert.ToInt32((decimal)image.Height * newWidth / image.Width);
    }
    else if ((decimal)image.Width / image.Height < (decimal)newWidth / newHeight)
    {
      newWidth = Convert.ToInt32((decimal)image.Width * newHeight / image.Height);      
    }
    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(Server.MapPath("~/") + DateTime.Now.ToString("yyyyMMddHHmmss") + fileExt);
    bmp.Dispose();
    image.Dispose();
  }
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
  <title>不经保存,直接生成上传图片的等比例的高质量缩略图</title>
</head>
<body>
  <form id="form1" runat="server">
  <asp:FileUpload ID="FileUpload1" runat="server" />
  <asp:Button ID="Button1" runat="server" onclick="Button1_Click" Text="上传并生成缩略图" />
  </form>
</body>
</html>

------解决方案--------------------
ashx中的方法

C# code
<%@ WebHandler Language="C#" Class="UploadFile" Debug="true" %>

using System;
using System.Web;

public class UploadFile : IHttpHandler {
    
public void ProcessRequest (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)
    {
      newHeight = Convert.ToInt32((decimal)image.Height * newWidth / image.Width);
    }
    else if ((decimal)image.Width / image.Height < (decimal)newWidth / newHeight)
    {
      newWidth = Convert.ToInt32((decimal)image.Width * newHeight / image.Height);
    }
    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.CompositingQual