using System;
using System.Collections;
using System.Web;
using System.IO;
using System.Globalization;
using LitJson;
public class Upload : IHttpHandler
{
private HttpContext context;
public void ProcessRequest(HttpContext context)
{
//获得文件名
String aspxUrl = context.Request.Path.Substring(0, context.Request.Path.LastIndexOf("/") + 1);
//文件保存目录路径
String savePath = "../attached/";
//文件保存目录URL
String saveUrl = aspxUrl + "../attached/";
//定义允许上传的文件扩展名
Hashtable extTable = new Hashtable();
extTable.Add("image", "gif,jpg,jpeg,png,bmp");
extTable.Add("flash", "swf,flv");
extTable.Add("media", "swf,flv,mp3,wav,wma,wmv,mid,avi,mpg,asf,rm,rmvb");
extTable.Add("file", "doc,docx,xls,xlsx,ppt,htm,html,txt,zip,rar,gz,bz2");
//最大文件大小
int maxSize = 52428800;
this.context = context;
//获取文件
HttpPostedFile imgFile = context.Request.Files["imgFile"];
if (imgFile == null)
{
showError("请选择文件。");
}
String dirPath = context.Server.MapPath(savePath);
if (!Directory.Exists(dirPath))
{
showError("上传目录不存在。");
}
//获取文件类型
String dirName = context.Request.QueryString["dir"];
if (String.IsNullOrEmpty(dirName)) {
dirName = "image";
}
if (!extTable.ContainsKey(dirName)) {
showError("目录名不正确。");
}
String fileName = imgFile.FileName;
String fileExt = Path.GetExtension(fileName).ToLower();
if (imgFile.InputStream == null || imgFile.InputStream.Length > maxSize)
{
showError("上传文件大小超过限制。");
}
if (String.IsNullOrEmpty(fileExt) || Array.IndexOf(((String)extTable[dirName]).Split(','), fileExt.Substring(1).ToLower()) == -1)
{
showError("上传文件扩展名是不允许的扩展名。n只允许" + ((String)extTable[dirName]) + "格式。");
}
//创建文件夹
dirPath += dirName + "/";
saveUrl += dirName + "/";
if (!Directory.Exists(dirPath)) {
Directory.CreateDirectory(dirPath);
}
String ymd = DateTime.Now.ToString("yyyyMMdd", DateTimeFormatInfo.InvariantInfo);
dirPath += ymd + "/";
saveUrl += ymd + "/";
if (!Directory.Exists(dirPath)) {
Directory.CreateDirectory(dirPath);
}
//生成文件名
String newFileName = DateTime.Now.ToString("yyyyMMddHHmmss_ffff", DateTimeFormatInfo.InvariantInfo) + fileExt;
//文件保存的物理里地址
String filePath = dirPath + newFileName;
//保存文件
imgFile.SaveAs(filePath);
//文件相对地址
String fileUrl = saveUrl + newFileName;
//设置返回信息，返回值是以JSON数组形式返回的，即前面是key,后面是value
Hashtable hash = new Hashtable();
hash["error"] = 0;
//返回原图的地址
hash["url"] = fileUrl;
/*
还可设置多个返回结果,比如图片的宽，高等
如：hash["width"]=100;
*/
//判断上传的文件类型
if (context.Request.QueryString["dir"] == "image")
{
//请求中有width这个参数表示图片需要进行处理
if (context.Request.QueryString["width"] != null)
{ //缩略图相对地址
string thumbfilePath = dirPath + "Thumb" + newFileName;
int width=Convert.ToInt32(context.Request.QueryString["width"]);
int height=Convert.ToInt32(context.Request.QueryString["height"]);
//获得原始图片的宽和高
System.Drawing.Image originalImage = System.Drawing.Image.FromFile(filePath);
int ow = originalImage.Width;
int oh = originalImage.Height;
//如果原图的尺寸比缩略图要求的尺寸小,则不进行任何处理
if (width <= ow && height <= oh)
{
string smillUrl = fileUrl;
//返回缩略图的地址
hash["thumUrl"] = smillUrl;
}
else
{
//生成缩略图
if (MakeThumbnail(filePath, thumbfilePath, width, height, "HW"))
{
string smillUrl = saveUrl + "Thumb" + newFileName;
hash["thumUrl"] = smillUrl;
}
else
{
showError("生成缩略图失败");
}
}
}
}
context.Response.AddHeader("Content-Type", "text/html; charset=UTF-8");
context.Response.Write(JsonMapper.ToJson(hash));
context.Response.End();
}
//返回错误消息
private void showError(string message)
{
Hashtable hash = new Hashtable();
hash["error"] = 1;
hash["message"] = message;
context.Response.AddHeader("Content-Type", "text/html; charset=UTF-8");
context.Response.Write(JsonMapper.ToJson(hash));
context.Response.End();
}
public bool IsReusable
{
get
{
return true;
}
}
/// <summary>
/// 生成缩略图
/// </summary>
/// <param name="originalImagePath">源图路径（物理路径）</param>
/// <param name="thumbnailPath">缩略图路径（物理路径）</param>
/// <param name="width">缩略图宽度</param>
/// <param name="height">缩略图高度</param>
/// <param name="mode">生成缩略图的方式</param>
public static bool MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)
{
System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath);
int towidth = width;
int toheight = height;
int x = 0;
int y = 0;
int ow = originalImage.Width;
int oh = originalImage.Height;
switch (mode)
{
case "HW"://指定高宽缩放（可能变形）
break;
case "W"://指定宽，高按比例
toheight = originalImage.Height * width / originalImage.Width;
break;
case "H"://指定高，宽按比例
towidth = originalImage.Width * height / originalImage.Height;
break;
case "Cut"://指定高宽裁减（不变形）
if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight)
{
oh = originalImage.Height;
ow = originalImage.Height * towidth / toheight;
y = 0;
x = (originalImage.Width - ow) / 2;
}
else
{
ow = originalImage.Width;
oh = originalImage.Width * height / towidth;
x = 0;
y = (originalImage.Height - oh) / 2;
}
break;
default:
break;
}
//新建一个bmp图片
System.Drawing.Image bitmap = new System.Drawing.Bitmap(towidth, toheight);
//新建一个画板
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitmap);
//设置高质量插值法
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
//设置高质量,低速度呈现平滑程度
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
//清空画布并以透明背景色填充
g.Clear(System.Drawing.Color.Transparent);
//在指定位置并且按指定大小绘制原图片的指定部分
g.DrawImage(originalImage, new System.Drawing.Rectangle(0, 0, towidth, toheight),
new System.Drawing.Rectangle(x, y, ow, oh),
System.Drawing.GraphicsUnit.Pixel);
try
{
//以jpg格式保存缩略图
bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg);
return true;
}
catch (System.Exception e)
{
return false;
throw e;
}
finally
{
originalImage.Dispose();
bitmap.Dispose();
g.Dispose();
}
}
}
前台调用就很简单了，这里也贴一下：
KindEditor.ready(function (K) {
var uploadbutton = K.uploadbutton({
button: K('#uploadButton')[0],
//上传的文件类型
fieldName: 'imgFile',
//注意后面的参数，dir表示文件类型，width表示缩略图的宽，height表示高
url: '../Editer/asp.net/upload_json.ashx?dir=image&width=65&height=61',
afterUpload: function (data) {
if (data.error === 0) {
alert('图片上传成功');
//取返回值,注意后台设置的key,如果要取原值
//取缩略图地址
var thumUrl = K.formatUrl(data.thumUrl, 'absolute');
//取原图地址
//var url=k.fromUrl(data.Url,'absolute');
K('#txtPic').val(thumUrl);
} else {
alert(data.message);
}
},
afterError: function (str) {
alert('自定义错误信息: ' + str);
}
});
uploadbutton.fileBox.change(function (e) {
uploadbutton.submit();
});
});
|
