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Vue + Element UI圖片上傳控件使用詳解

更新時(shí)間：2019年08月20日 10:46:19 作者：天青色等煙雨11

這篇文章主要為大家詳細(xì)介紹了Vue + Element UI圖片上傳控件的使用方法，具有一定的參考價(jià)值，感興趣的小伙伴們可以參考一下

上一篇 Vue +Element UI +vue-quill-editor 富文本編輯器及插入圖片自定義主要是寫了富文本編輯器的自定義及編輯器中圖片的上傳并插入到編輯內(nèi)容，這篇文章單獨(dú)介紹一下element UI 圖片上傳控件的使用。首先要安裝element并中引入，安裝引入過程這里不再贅述。

1.引用element 上傳控件。

<el-upload
 action="/mgr/common/imgUpload"http://這里需要配置一下文件上傳地址（跨域）
 list-type="picture-card"
 accept="image/*"
 :limit="imgLimit"
 :file-list="productImgs"
 :multiple="isMultiple"
 :on-preview="handlePictureCardPreview"
 :on-remove="handleRemove"
 :on-success="handleAvatarSuccess"
 :before-upload="beforeAvatarUpload"
 :on-exceed="handleExceed"
 :on-error="imgUploadError">
 <i class="el-icon-plus"></i>
 </el-upload>
 <el-dialog :visible.sync="dialogVisible">
 <img width="100%" :src="dialogImageUrl" alt="">
 </el-dialog>

2.js

export default {
 data() {
 return {
 dialogImageUrl: '',
 dialogVisible: false,
 productImgs: [],
 isMultiple: true,
 imgLimit: 6
 }
 },
 methods: {
 handleRemove(file, fileList) {//移除圖片
 console.log(file, fileList);
 },
 handlePictureCardPreview(file) {//預(yù)覽圖片時(shí)調(diào)用
 console.log(file);
 this.dialogImageUrl = file.url;
 this.dialogVisible = true;
 },
 
 beforeAvatarUpload(file) {//文件上傳之前調(diào)用做一些攔截限制
 console.log(file);
 const isJPG = true;
 // const isJPG = file.type === 'image/jpeg';
 const isLt2M = file.size / 1024 / 1024 < 2;
 
 // if (!isJPG) {
 // this.$message.error('上傳頭像圖片只能是 JPG 格式!');
 // }
 if (!isLt2M) {
  this.$message.error('上傳圖片大小不能超過 2MB!');
 }
 return isJPG && isLt2M;
 },
 handleAvatarSuccess(res, file) {//圖片上傳成功
 console.log(res);
 console.log(file);
 this.imageUrl = URL.createObjectURL(file.raw);
 },
 handleExceed(files, fileList) {//圖片上傳超過數(shù)量限制
 this.$message.error('上傳圖片不能超過6張!');
 console.log(file, fileList);
 },
 imgUploadError(err, file, fileList){//圖片上傳失敗調(diào)用
 console.log(err)
 this.$message.error('上傳圖片失敗!');
 }
 }
 }

3.controller

 @RequestMapping(value = "/imgUpload")
 public Wrapper imgUpload(HttpServletRequest req, MultipartHttpServletRequest multiReq)
  throws IOException {
 System.out.println("---" + fileUploadPath);//我這里用的springboot 在application.properties中配置，使用@Value 獲取的文件上傳目錄
 
 MultipartFile file = multiReq.getFile("file");
 String originalFilename = file.getOriginalFilename();
 String suffix = originalFilename.substring(originalFilename.indexOf("."));
 String localFileName = MD5Util.md5(file.getInputStream()) + suffix;
 File localFile = new File(fileUploadPath + localFileName);
 if (!localFile.exists()) {
  localFile.createNewFile();
 
  FileOutputStream fos = new FileOutputStream(
   localFile);
  FileInputStream fs = (FileInputStream) multiReq.getFile("img").getInputStream();
  byte[] buffer = new byte[1024];
  int len = 0;
  while ((len = fs.read(buffer)) != -1) {
  fos.write(buffer, 0, len);
  }
  fos.close();
  fs.close();
 
 } else {
  log.info("文件已存在?。?);
 }
 
 return WrapMapper.wrap(
  Wrapper.SUCCESS_CODE,
  Wrapper.SUCCESS_MESSAGE,
  "http://localhost:8080/img/" + localFileName);//這里是我執(zhí)行封裝的返回結(jié)果，也可以使用map,
 }

4.MD5工具類

import java.io.*;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
 
public class MD5Util {
 
 private static char[] Digit = {'0', '1', '2', '3', '4', '5', '6', '7', '8',
  '9', 'a', 'b', 'c', 'd', 'e', 'f'};
 
 public static String getMd5Sum(String inputStr)
  throws NoSuchAlgorithmException {
 MessageDigest digest = MessageDigest.getInstance("MD5");
 byte[] inputStrByte = inputStr.getBytes();
 digest.update(inputStrByte, 0, inputStrByte.length);
 
 byte[] md5sum = digest.digest();
 
 StringBuffer sb = new StringBuffer();
 for (int i = 0; i < 16; i++) {
  char[] ob = new char[2];
  ob[0] = Digit[md5sum[i] >> 4 & 0x0F];
  ob[1] = Digit[md5sum[i] & 0x0F];
  String s = new String(ob);
  sb.append(s);
 }
 
 return sb.toString();
 }
 
 /**
 * 對(duì)字符串進(jìn)行 MD5 加密
 *
 * @param str
 *  待加密字符串
 *
 * @return 加密后字符串
 */
 public static String md5(String str) {
 MessageDigest md5 = null;
 try {
  md5 = MessageDigest.getInstance("MD5");
  md5.update(str.getBytes("UTF-8"));
 } catch (NoSuchAlgorithmException e) {
  throw new RuntimeException(e.getMessage());
 } catch (UnsupportedEncodingException e) {
  throw new RuntimeException(e.getMessage());
 }
 byte[] encodedValue = md5.digest();
 int j = encodedValue.length;
 char finalValue[] = new char[j * 2];
 int k = 0;
 for (int i = 0; i < j; i++) {
  byte encoded = encodedValue[i];
  finalValue[k++] = Digit[encoded >> 4 & 0xf];
  finalValue[k++] = Digit[encoded & 0xf];
 }
 
 return new String(finalValue);
 }
 
 /**
 * 簽名字符串
 *
 * @param text
 *  需要簽名的字符串
 * @param sign
 *  簽名結(jié)果
 * @return 簽名結(jié)果
 */
 public static boolean verify(String text, String sign) {
 String mysign = md5(text);
 if (mysign.equals(sign)) {
  return true;
 } else {
  return false;
 }
 }
 
 /**
 * 對(duì)文件進(jìn)行 MD5 加密
 *
 * @param file
 *  待加密的文件
 *
 * @return 文件加密后的 MD5 值
 * @throws IOException
 */
 public static String md5(File file) throws IOException {
 FileInputStream is = new FileInputStream(file);
 return md5(is);
 
 }
 
 
 public static String md5(InputStream inputStream) throws IOException {
 
 MessageDigest md5 = null;
 try {
  md5 = MessageDigest.getInstance("MD5");
  int n = 0;
  byte[] buffer = new byte[1024];
  do {
  n = inputStream.read(buffer);
  if (n > 0) {
   md5.update(buffer, 0, n);
  }
  } while (n != -1);
  inputStream.skip(0);
 } catch (NoSuchAlgorithmException e) {
  throw new RuntimeException(e.getMessage());
 } finally {
  inputStream.close();
 }
 
 byte[] encodedValue = md5.digest();
 
 int j = encodedValue.length;
 char finalValue[] = new char[j * 2];
 int k = 0;
 for (int i = 0; i < j; i++) {
  byte encoded = encodedValue[i];
  finalValue[k++] = Digit[encoded >> 4 & 0xf];
  finalValue[k++] = Digit[encoded & 0xf];
 }
 return new String(finalValue);
 }
}

5.效果