vue-cli结合Element-ui基于cropper.js封装vue实现图片裁剪组件功能

前端工作中，经常需要图片裁剪的场景，cropper.js是一款优秀的前端插件，api十分丰富。

本文是在vue-cli项目下封装图片裁剪插件，效果图如下：

话不多说，看步骤吧。

第一步：准备开发环境

cropper.js是基于jquery的，所以要先安装jquery

执行命令：

  npm  install --save-dev jquery cropper

 为webpack配置添加jquery的映射

修改webpack.base.conf.js配置，添加标红的一行

第二步：新建图片裁剪组件

index.vue内容：

由于用了element-ui,其中布局就引用了element-ui的组件

 template:

style:

 
 
 .avatar-wrapper{
 width: 100%;
 height: 100%;
 overflow: hidden;
 }
 .cropper-container {
 direction: ltr;
 font-size: 0;
 line-height: 0;
 position: relative;
 -ms-touch-action: none;
 touch-action: none;
 -webkit-user-select: none;
 -moz-user-select: none;
 -ms-user-select: none;
 user-select: none;
 }
 .cropper-container img {
 display: block;
 height: 100%;
 image-orientation: 0deg;
 max-height: none !important;
 max-width: none !important;
 min-height: 0 !important;
 min-width: 0 !important;
 width: 100%;
 }
 .cropper-wrap-box,
 .cropper-canvas,
 .cropper-drag-box,
 .cropper-crop-box,
 .cropper-modal {
 bottom: 0;
 left: 0;
 position: absolute;
 right: 0;
 top: 0;
 }
 .cropper-wrap-box,
 .cropper-canvas {
 overflow: hidden;
 }
 .cropper-drag-box {
 background-color: #fff;
 opacity: 0;
 }
 .cropper-modal {
 background-color: #000;
 opacity: .5;
 }
 .cropper-view-box {
 display: block;
 height: 100%;
 outline-color: rgba(51, 153, 255, 0.75);
 outline: 1px solid #39f;
 overflow: hidden;
 width: 100%;
 }
 .cropper-dashed {
 border: 0 dashed #eee;
 display: block;
 opacity: .5;
 position: absolute;
 }
 .cropper-dashed.dashed-h {
 border-bottom-width: 1px;
 border-top-width: 1px;
 height: 33.33333%;
 left: 0;
 top: 33.33333%;
 width: 100%;
 }
 .cropper-dashed.dashed-v {
 border-left-width: 1px;
 border-right-width: 1px;
 height: 100%;
 left: 33.33333%;
 top: 0;
 width: 33.33333%;
 }
 .cropper-center {
 display: block;
 height: 0;
 left: 50%;
 opacity: .75;
 position: absolute;
 top: 50%;
 width: 0;
 }
 .cropper-center:before,
 .cropper-center:after {
 background-color: #eee;
 content: ' ';
 display: block;
 position: absolute;
 }
 .cropper-center:before {
 height: 1px;
 left: -3px;
 top: 0;
 width: 7px;
 }
 .cropper-center:after {
 height: 7px;
 left: 0;
 top: -3px;
 width: 1px;
 }
 .cropper-face,
 .cropper-line,
 .cropper-point {
 display: block;
 height: 100%;
 opacity: .1;
 position: absolute;
 width: 100%;
 }
 .cropper-face {
 background-color: #fff;
 left: 0;
 top: 0;
 }
 .cropper-line {
 background-color: #39f;
 }
 .cropper-line.line-e {
 cursor: e-resize;
 right: -3px;
 top: 0;
 width: 5px;
 }
 .cropper-line.line-n {
 cursor: n-resize;
 height: 5px;
 left: 0;
 top: -3px;
 }
 .cropper-line.line-w {
 cursor: w-resize;
 left: -3px;
 top: 0;
 width: 5px;
 }
 .cropper-line.line-s {
 bottom: -3px;
 cursor: s-resize;
 height: 5px;
 left: 0;
 }
 .cropper-point {
 background-color: #39f;
 height: 5px;
 opacity: .75;
 width: 5px;
 }
 .cropper-point.point-e {
 cursor: e-resize;
 margin-top: -3px;
 right: -3px;
 top: 50%;
 }
 .cropper-point.point-n {
 cursor: n-resize;
 left: 50%;
 margin-left: -3px;
 top: -3px;
 }
 .cropper-point.point-w {
 cursor: w-resize;
 left: -3px;
 margin-top: -3px;
 top: 50%;
 }
 .cropper-point.point-s {
 bottom: -3px;
 cursor: s-resize;
 left: 50%;
 margin-left: -3px;
 }
 .cropper-point.point-ne {
 cursor: ne-resize;
 right: -3px;
 top: -3px;
 }
 .cropper-point.point-nw {
 cursor: nw-resize;
 left: -3px;
 top: -3px;
 }
 .cropper-point.point-sw {
 bottom: -3px;
 cursor: sw-resize;
 left: -3px;
 }
 .cropper-point.point-se {
 bottom: -3px;
 cursor: se-resize;
 height: 20px;
 opacity: 1;
 right: -3px;
 width: 20px;
 }
 @media (min-width: 768px) {
 .cropper-point.point-se {
  height: 15px;
  width: 15px;
 }
 }
 @media (min-width: 992px) {
 .cropper-point.point-se {
  height: 10px;
  width: 10px;
 }
 }
 @media (min-width: 1200px) {
 .cropper-point.point-se {
  height: 5px;
  opacity: .75;
  width: 5px;
 }
 }
 .cropper-point.point-se:before {
 background-color: #39f;
 bottom: -50%;
 content: ' ';
 display: block;
 height: 200%;
 opacity: 0;
 position: absolute;
 right: -50%;
 width: 200%;
 }
 .cropper-invisible {
 opacity: 0;
 }
 .cropper-bg {
 background-image: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQAQMAAAAlPW0iAAAAA3NCSVQICAjb4U/gAAAABlBMVEXMzMz////TjRV2AAAACXBIWXMAAArrAAAK6wGCiw1aAAAAHHRFWHRTb2Z0d2FyZQBBZG9iZSBGaXJld29ya3MgQ1M26LyyjAAAABFJREFUCJlj+M/AgBVhF/0PAH6/D/HkDxOGAAAAAElFTkSuQmCC');
 }
 .cropper-hide {
 display: block;
 height: 0;
 position: absolute;
 width: 0;
 }
 .cropper-hidden {
 display: none !important;
 }
 .cropper-move {
 cursor: move;
 }
 .cropper-crop {
 cursor: crosshair;
 }
 .cropper-disabled .cropper-drag-box,
 .cropper-disabled .cropper-face,
 .cropper-disabled .cropper-line,
 .cropper-disabled .cropper-point {
 cursor: not-allowed;
 }
 .avatar-view {
 display: block;
 margin: 15% auto 5%;
 height: 220px;
 width: 220px;
 border: 3px solid #fff;
 border-radius: 5px;
 box-shadow: 0 0 5px rgba(0,0,0,.15);
 cursor: pointer;
 overflow: hidden;
 }
 .avatar-view img {
 width: 100%;
 }
 .avatar-body {
 padding-right: 15px;
 padding-left: 15px;
 }
 .avatar-upload {
 overflow: hidden;
 }
 .avatar-upload label {
 display: block;
 float: left;
 clear: left;
 width: 100px;
 }
 .avatar-upload input {
 display: block;
 margin-left: 110px;
 }
 .avatar-alert {
 margin-top: 10px;
 margin-bottom: 10px;
 }
 .avatar-wrapper {
 height: 364px;
 width: 100%;
 margin-top: 15px;
 box-shadow: inset 0 0 5px rgba(0,0,0,.25);
 background-color: #fcfcfc;
 overflow: hidden;
 }
 .avatar-wrapper img {
 display: block;
 height: auto;
 max-width: 100%;
 }
 .avatar-preview {
 float: left;
 margin-top: 15px;
 margin-right: 15px;
 border: 1px solid #eee;
 border-radius: 4px;
 background-color: #fff;
 overflow: hidden;
 }
 .avatar-preview:hover {
 border-color: #ccf;
 box-shadow: 0 0 5px rgba(0,0,0,.15);
 }
 .avatar-preview img {
 width: 100%;
 }
 .avatar-preview-round{
 border-radius: 50%;
 }
 .preview-lg {
 height: 184px;
 width: 184px;
 margin-top: 15px;
 }
 .preview-md {
 height: 100px;
 width: 100px;
 }
 .preview-sm {
 height: 50px;
 width: 50px;
 }
 @media (min-width: 992px) {
 .avatar-preview {
  float: none;
 }
 }
 .avatar-btns {
 margin-top: 30px;
 margin-bottom: 15px;
 }
 .avatar-btns .btn-group {
 margin-right: 5px;
 }

script:

第三步：父组件引用子组件

用了element-ui中的 el-dialog组件，此时el-dialog组件为父组件

在父组件中引入子组件

import cropper from '@/components/Cropper/index'

template: