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The content of this article is about the browser displaying the preview of the local image and calling the back-end interface to upload the image to the server. It has certain reference value. Now I share it with everyone. Friends in need can refer to it. Let’s take a look
1. jsp page
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%><%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title></title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <META HTTP-EQUIV="pragma" CONTENT="no-cache"> <META HTTP-EQUIV="Cache-Control" CONTENT="no-cache, must-revalidate"> <META HTTP-EQUIV="expires" CONTENT="0"> <!-- 引入js --> <script type="text/javascript" src="<%=request.getContextPath()%>/js/jquery.js"></script> <script type="text/javascript" src="<%=request.getContextPath()%>/js/jquery.min.js"></script> <body> <p id="enteringInfor"> <form id="uploadForm" > <p class="formItem" style="float:left"> <p class="itemBlock"> <p style="display:inline-block;float:left" class="selectContainer"> <span class="txtBox">姓名</span> <input type="text" class="select" name="realName" id="realName" placeholder="请输入姓名" style="width:200px;"> </p> </p> <p class="itemBlock"> <p style="display:inline-block;float:left" class="selectContainer"> <span class="txtBox">性别</span> <select class="select" name="gender" id="gender" > <option value="1">男</option> <option value="2">女</option> </select> </p> </p> </p> <p class="formItem" style="float:right;margin-top:50px;"> <p class="picture"> <p class="layui-upload"> <p class="layui-upload-list" id="localImag"> <img class="layui-upload-img" id="userPic" style="max-width:90%" alt="How to get local images to display in the browser and upload them to the server in js" > <p id="demoText"></p> </p> <p class="btn btn-primary fileinput-button" style="width:332px;position:absolute;bottom:0px"> <span class="uploadTxt">上传图片</span> <input class="form-control layui-btn" id="entrustPicUpload" type="file" name="entImg" onchange="getPhoto(this)" /> </p> </p> </p> </p> </form> <p class="modelEditorBottom" style="padding-left:24px;text-align:center;height:70px;line-height:70px;border:none;width:100%;overflow:hidden;zoom:1"> <button class="buttons adminButton" onclick="saveUser()">保存</button> </p> <input type="hidden" name="userId" id="userId"/> </p><script> var imgurl = ""; function getPhoto(node) { var imgURL = ""; try{ var file = null; if(node.files && node.files[0] ){ file = node.files[0]; }else if(node.files && node.files.item(0)) { file = node.files.item(0); } //Firefox 因安全性问题已无法直接通过input[file].value 获取完整的文件路径 try{ imgURL = file.getAsDataURL(); }catch(e){ imgRUL = window.URL.createObjectURL(file); } }catch(e){ if (node.files && node.files[0]) { var reader = new FileReader(); reader.onload = function (e) { imgURL = e.target.result; }; reader.readAsDataURL(node.files[0]); } } creatImg(imgRUL);//显示图片 return imgURL; } function creatImg(imgRUL){ document.getElementById("userPic").src = imgRUL; $('#userPic').viewer({ url: 'src', }); } //保存 function saveUser(){ //数据判断 var realName=$("#realName").val(); if(realName==null||realName==''){ layer.msg('用户名不能为空!',{icon : 7,time:1000}); return ; } var imgSrc = $("#userPic").attr("src"); if(imgSrc == "" || imgSrc==null){ layer.msg('请上传图片!',{icon : 7,time:1000}); return ; } var formData = new FormData($("#uploadForm")[0]); $.ajax({ url : "../addUser", type: 'POST', data: formData, async: false, cache: false, contentType: false, processData: false, success : function(data) { var obj = JSON.parse(data); layer.msg('保存成功!', {icon : 6,time : 2000}); }, error : function(data) { layer.msg('保存失败!', {icon : 5,time : 2000}); } }); } </script> </body></html>
2. Controller interface
/** * 添加用户 * @param session * @param request * @param response * @throws IOException */ @RequestMapping(value = "/addUser", method = RequestMethod.POST) public void addUser(MultipartFile entImg,HttpSession session, HttpServletRequest request, HttpServletResponse response) throws IOException { String realName = request.getParameter("realName");//姓名 String gender = request.getParameter("gender");// 性别 //调用工具类上传图片 String userPic = FileUtils.uploadUser(entImg, request); TestUser testUser = new TestUser(); testUser.setRealName(realName); testUser.setGender(Integer.parseInt(gender)); testUser.setUserPic(userPic); // 添加人员信息及图片url到数据库 int res= userService.insertUser(testUser); if (res > 0) { writeJSON(response, res); } else { writeJSON(response,null); } }
3. Tools Category
public class FileUtils { FILES_PATH("files_path"); // 此路径存放于jdbc.properties配置文件中,例如:files_path=D:/uploadImgs private static final String path = PropertiesUtil.get(FILES_PATH)+"/user"; /** * 上传图片URL * @param fileName * @param request * @return */ public static String getPath(String fileName,HttpServletRequest request) { String ip=IpUtil.getIP(); int port=request.getLocalPort(); StringBuilder sb=new StringBuilder(); sb.append("http://"); sb.append(ip); sb.append(":"); sb.append(port); sb.append("/uploadImgs/user/"); sb.append(fileName); return sb.toString(); } /** * 以时间戳对上传文件进行重新命名 * @param file * @return */ public static String renameFile(MultipartFile file) { if(file!=null) { Long date=new Date().getTime(); String fileRealName=file.getOriginalFilename(); String prefix=fileRealName.substring(fileRealName.lastIndexOf(".")+1); String fileName = date.toString()+"."+prefix; return fileName; } return null; } /** * 图片上传 * @param file * @param fileName */ public static String uploadUser(MultipartFile file, HttpServletRequest request) { // 重命名 String renameFile = FileUtils.renameFile(file); // 图片名 String picPath = FileUtils.getPath(renameFile, request); // 上传 File targetFile = new File(borpath, renameFile); if (!targetFile.exists() && !targetFile.isDirectory()) { targetFile.mkdirs(); } try { file.transferTo(targetFile); } catch (Exception e) { e.printStackTrace(); } return picPath; } }
4. Effect
3. After the picture is uploaded successfully, save it to the specified location Under the folder
4. Database data
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