先给大家展示下效果图：
页面代码
里面用户的uuid是写死的test
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%><!DOCTYPE><html lang="en"><head><title>用户头像剪裁</title><meta http-equiv="Content-type" content="text/html;charset=UTF-8" /><link rel="stylesheet" href="resources/Jcrop/css/jquery.Jcrop.css"><link rel="stylesheet" href="resources/css/photo.css"><script src="resources/js/jquery.min.js"></script><script src="resources/Jcrop/js/jquery.Jcrop.js"></script><script src="resources/js/ajaxfileupload.js"></script></head><body><div><div><div><div><div><h1>头像剪裁</h1></div><img src="resources/img/test.jpg" id="target" /><div id="preview-pane" ><div><img src="resources/img/test.jpg"/></div ><div style='float:left;display:inline;'><a class='btn_addPic' href="javascript:void(0);"><span><EM>+</EM>添加图片</span> <input id="upload_image" type="file" name="upimage" accept="image/*" class = "filePrew"/></a></div><div style='float:right;display:inline;'><a class='btn_addPic' href="javascript:void(0);" onclick='submit()'><span>提交</span> </a></div></div></div></div></div></div></body><script type="text/javascript">var global_api = "";var boundx ="";//页面图片宽度var boundy ="";//页面图片高度var tag = false;$(function() {// Create variables (in this scope) to hold the API and image size//创建变量(在这个范围)的API和图像大小var jcrop_api,// Grab some information about the preview pane//获取一些信息预览窗格$preview = $('#preview-pane'),$pcnt = $('#preview-pane .preview-container'),$pimg = $('#preview-pane .preview-container img'),xsize = $pcnt.width(),ysize = $pcnt.height();$('#target').Jcrop({onChange: updatePreview,onSelect: updatePreview,aspectRatio: xsize / ysize},function(){// Use the API to get the real image size//使用API来获得真实的图像大小var bounds = this.getBounds();boundx = bounds[0];boundy = bounds[1];// Store the API in the jcrop_api variable//jcrop_api变量中存储APIjcrop_api = this;// Move the preview into the jcrop container for css positioning//预览进入jcrop容器css定位$preview.appendTo(jcrop_api.ui.holder);});function updatePreview(c){if (parseInt(c.w) > 0)global_api=c;{var rx = xsize / c.w;var ry = ysize / c.h;$pimg.css({width: Math.round(rx * boundx) + 'px',height: Math.round(ry * boundy) + 'px',marginLeft: '-' + Math.round(rx * c.x) + 'px',marginTop: '-' + Math.round(ry * c.y) + 'px'});}};//=======选择图片回显===============$('#upload_image').change(function(event) {// 根据这个 <input> 获取文件的 HTML5 js 对象var files = event.target.files, file; if (files && files.length > 0) {// 获取目前上传的文件file = files[0];// 下面是关键的关键，通过这个 file 对象生成一个可用的图像 URL// 获取 window 的 URL 工具var URL = window.URL || window.webkitURL;// 通过 file 生成目标 urlvar imgURL = URL.createObjectURL(file);// 用这个 URL 产生一个 <img> 将其显示出来$('.jcrop-holder img').attr('src', imgURL);$('.preview-container img').attr('src', imgURL);}});//=============是否选择了本地图片==================$("#upload_image").change(function(){tag=true;});});//========================================================//======图片保存===========function submit(){if(tag&&global_api != ""){ajaxFileUpload();}else{alert('你是不是什么事情都没干？');}}//ajax文件上传function ajaxFileUpload() {$.ajaxFileUpload({url: 'uploadphoto', //用于文件上传的服务器端请求地址secureuri: false, //一般设置为falsefileElementId: 'upload_image', //文件上传空间的id属性dataType: 'json', //返回值类型 一般设置为jsondata:{x:global_api.x,y:global_api.y,w:global_api.w,h:global_api.h,pw:boundx,ph:boundy,unid:'test'}, //一同上传的数据 success: function (data){ //服务器成功响应处理函数if(data.result){alert('成功');}else{alert('失败');}window.location.reload();//刷新当前页面}});}</script></html>后台代码
@ResponseBody@RequestMapping("uploadphoto")public Map<String, Object> uploadPhoto(@RequestParam("upimage") MultipartFile imageFile, HttpServletRequest request,HttpServletResponse response) throws Exception {Map<String, Object> result = new HashMap<String, Object>();boolean tag =false;String unid = request.getParameter("unid");String x = request.getParameter("x");String y = request.getParameter("y");String h = request.getParameter("h");String w = request.getParameter("w");// 页面实际图片宽高String pheight = request.getParameter("ph");String pweight = request.getParameter("pw");// 切图参数int imageX = Integer.parseInt(x);int imageY = Integer.parseInt(y);int imageH = Integer.parseInt(h);int imageW = Integer.parseInt(w);int srcH = Integer.parseInt(pheight);int srcW = Integer.parseInt(pweight);String realPath = request.getSession().getServletContext().getRealPath("/");String resourcePath = "resources/uploadImages/";try {if (imageFile != null) {if (FileUploadUtil.allowUpload(imageFile.getContentType())) {// 这里开始截取操作byte[] b = ImageCut.imgCut(imageFile.getInputStream(), imageX, imageY, imageW, imageH, srcW, srcH);if (b != null) {// 存入数据库User user = userService.selectByPrimaryKey(unid);user.setPhoto(b);tag = (userService.updateByPrimaryKeySelective(user)==1)?tag=true:tag;result.put("result", tag);}}}} catch (Exception e) {e.printStackTrace();}result.put("result", tag);return result;}图像切割工具类
package com.ssm.demo.utils;import java.awt.Graphics;import java.awt.Image;import java.awt.Toolkit;import java.awt.image.BufferedImage;import java.awt.image.CropImageFilter;import java.awt.image.FilteredImageSource;import java.awt.image.ImageFilter;import java.io.ByteArrayOutputStream;import java.io.InputStream;import javax.imageio.ImageIO;public class ImageCut {/*** 截取图片* * @param srcImageFile* 原图片地址* @param x* 截取时的x坐标* @param y* 截取时的y坐标* @param desWidth* 截取的宽度* @param desHeight* 截取的高度* @param srcWidth* 页面图片的宽度* @param srcHeight* 页面图片的高度* */public static byte[] imgCut(InputStream input, int x, int y, int desWidth, int desHeight, int srcWidth,int srcHeight) {try {Image img;ImageFilter cropFilter;BufferedImage bi = ImageIO.read(input);if (srcWidth >= desWidth && srcHeight >= desHeight) {Image image = bi.getScaledInstance(srcWidth, srcHeight, Image.SCALE_DEFAULT);cropFilter = new CropImageFilter(x, y, desWidth, desHeight);img = Toolkit.getDefaultToolkit().createImage(new FilteredImageSource(image.getSource(), cropFilter));BufferedImage tag = new BufferedImage(desWidth, desHeight, BufferedImage.TYPE_INT_RGB);Graphics g = tag.getGraphics();g.drawImage(img, 0, 0, null);g.dispose();// 输出文件ByteArrayOutputStream out = new ByteArrayOutputStream();ImageIO.write(tag, "JPEG", out);return out.toByteArray();}} catch (Exception e) {e.printStackTrace();}return null;}}以上所述是小编给大家介绍的JCrop+ajaxUpload 图像切割上传的实例代码，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对武林网网站的支持！