1、说明
接上一篇文章asp.net uploadify实现多附件上传功能完成后，又突然用到头像上传并在线裁剪。在网上找个众多例子都没有符合要求的，有一篇文章写的不错,Asp.Net平台下的图片在线裁剪功能的实现代码(源码打包),大家可以看下
2、组成
首先说明一下代码实现所用到的技术，仅供参考：
开发工具：vs2010
目标框架：.NET framework3.5
jcrop：Jcrop.js v0.9.12
Uploadify：uploadify-v3.1
Jquery：jquery-1.9.0.js
最后我会将整个Demo上传，如果同学们的电脑上有开发环境可直接打开项目解决方案运行。
3、代码
Default.aspx（测试页面）
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="ImgJcrop._Default" %>在线裁剪
Uploadify.ashx（一般处理程序）
<%@ WebHandler Language="C#" Class="UploadifyUpload" %>
using System;
using System.Collections;
using System.Data;
using System.Web;
using System.Linq;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Web.SessionState;
using System.IO;
using System.Collections.Generic;
using System.Web.UI.WebControls;
using System.Text;
using System.Drawing;
using System.Drawing.Imaging;
public class UploadifyUpload : IHttpHandler, IRequiresSessionState
{
public void ProcessRequest(HttpContext context)
{
context.Response.ContentType = "text/plain";
context.Response.Charset = "utf-8";
string action = context.Request["action"];
switch (action)
{
case "upload":
//上传图片
upload(context);
break;
case "cutsaveimg":
//裁剪并保存
cutsaveimg(context);
break;
}
context.Response.End();
}
///
/// 上传图片
///
///
private void upload(HttpContext context)
{
HttpPostedFile postedFile = context.Request.Files["Filedata"];
if (postedFile != null)
{
string fileName, fileExtension;
int fileSize;
fileName = postedFile.FileName;
fileSize = postedFile.ContentLength;
if (fileName != "")
{
fileExtension = postedFile.FileName.Substring(postedFile.FileName.LastIndexOf('.'));
string strPath = context.Server.MapPath("/") + "\App_File\Upload\";//设置文件的路径
string strFileName = "upload" + DateTime.Now.ToString("yyyyMMddHHmmss") + fileExtension;
string strFileUrl = strPath + strFileName;//保存文件路径
if (!Directory.Exists(strPath))
{
Directory.CreateDirectory(strPath);
}
postedFile.SaveAs(strFileUrl);//先保存源文件
context.Response.Write("{"status":0,"message":"/App_File/Upload/" + strFileName + ""}");
}
else
{
context.Response.Write("{"status":1,"message":"上传失败！"}");
}
}
else
{
context.Response.Write("{"status":1,"message":"上传失败！"}");
}
}
///
/// 裁剪并保存图片
///
///
private void cutsaveimg(HttpContext context)
{
string strImgUrl = context.Request["strImgUrl"];
string strXone = context.Request["hidXone"];
string strYone = context.Request["hidYone"];
string strImgWidth = context.Request["hidImgWidth"];
string strImgHeight = context.Request["hidImgHeight"];
string[] urls = strImgUrl.Split('/');
string str_url = urls.Last();
try
{
string strOldFiel = context.Server.MapPath("~/App_File/Upload/");
string strNewFiel = context.Server.MapPath("~/App_File/Cut/");
string strOldUrl = Path.Combine(strOldFiel, str_url);
string strNewUrl = Path.Combine(strNewFiel, "cut" + DateTime.Now.ToString("yyyyMMddHHmmss") + "." + str_url.Split('.')[1]);
if (!Directory.Exists(strNewFiel))
{
Directory.CreateDirectory(strNewFiel);
}
int intStartX = int.Parse(strXone);
int intStartY = int.Parse(strYone);
int intWidth = int.Parse(strImgWidth);
int intHeight = int.Parse(strImgHeight);
CutGeneratedImage(intStartX, intStartY, intWidth, intHeight, strOldUrl, strNewUrl);
context.Response.Write("{"status":0,"message":"裁剪成功并保存！"}");
}
catch
{
context.Response.Write("{"status":1,"message":"裁剪失败！"}");
}
}
///
/// 裁剪图片
///
/// 要缩小裁剪图片宽度
/// 要缩小裁剪图片长度
/// 要处理图片路径
/// 处理完毕图片路径
public void CutGeneratedImage(int intStartX, int intStartY, int intWidth, int intHeight, string strOldImgUrl, string strNewImgUrl)
{
//上传标准图大小
int intStandardWidth = 120;
int intStandardHeight = 120;
int intReduceWidth = 0; // 缩小的宽度
int intReduceHeight = 0; // 缩小的高度
int intCutOutWidth = 0; // 裁剪的宽度
int intCutOutHeight = 0; // 裁剪的高度
int level = 100; //缩略图的质量 1-100的范围
//获得缩小，裁剪大小
if (intStandardHeight * intWidth / intStandardWidth > intHeight)
{
intReduceWidth = intWidth;
intReduceHeight = intStandardHeight * intWidth / intStandardWidth;
intCutOutWidth = intWidth;
intCutOutHeight = intHeight;
}
else if (intStandardHeight * intWidth / intStandardWidth < intHeight)
{
intReduceWidth = intStandardWidth * intHeight / intStandardHeight;
intReduceHeight = intHeight;
intCutOutWidth = intWidth;
intCutOutHeight = intHeight;
}
else
{
intReduceWidth = intWidth;
intReduceHeight = intHeight;
intCutOutWidth = intWidth;
intCutOutHeight = intHeight;
}
//通过连接创建Image对象
//System.Drawing.Image oldimage = System.Drawing.Image.FromFile(strOldImgUrl);
//oldimage.Save(Server.MapPath("tepm.jpg"));
//oldimage.Dispose();
//缩小图片
Bitmap bm = new Bitmap(strOldImgUrl);
//处理JPG质量的函数
ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();
ImageCodecInfo ici = null;
foreach (ImageCodecInfo codec in codecs)
{
if (codec.MimeType == "image/jpeg")
{
ici = codec;
break;
}
}
EncoderParameters ep = new EncoderParameters();
ep.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, (long)level);
//裁剪图片
Rectangle cloneRect = new Rectangle(intStartX, intStartY, intCutOutWidth, intCutOutHeight);
PixelFormat format = bm.PixelFormat;
Bitmap cloneBitmap = bm.Clone(cloneRect, format);
//保存图片
cloneBitmap.Save(strNewImgUrl, ici, ep);
bm.Dispose();
}
public bool IsReusable
{
get
{
return false;
}
}
}
4、最后奉上Demo
ImgJcrop
以上就是本文的全部内容，希望本文的内容对大家的学习或者工作能带来一定的帮助，如果有疑问大家可以留言交流，同时也希望多多支持考高分网！
