基于cropper.js封装vue实现在线图片裁剪组件功能

在router里面放置参数，然后通过调用route.params.xxx或者route.query.xxx进行获取

通过props进行通信

这里我们使用eventBus进行组件之间的通信

步骤

1.声明一个bus组件用于B组件把参数传递给A组件

//bus.js
import Vue from 'vue'; 
export default new Vue();

2.在A组件中引用bus组件，并实时监听其参数变化

// A.vue
import Bus from '../../components/bus/bus.js'
export default {
 components: { Bus },
 data () {},
 created: function () {
 Bus.$on('getTarget', imgToken => { 
 var _this = this;
 console.log(imgToken);
 ... 
 }); 
 }
}

3.B组件中同样引用bus组件，来把参数传给A组件

// B.vue
// 传参
Bus.$emit('getTarget', imgToken);

参考：

vue-$on
vue-$emit
vue.js之路(4)——vue2.0s中eventBus实现兄弟组件通信

vue选图截图插件完整代码

<template>
 <div class="myCropper-container">
 <div id="myCropper-workspace">
 <div class="myCropper-words" v-show="!imgCropperData.imgSrc">请点击按钮选择图片进行裁剪</div>
 </div>
 <div class="myCropper-preview" :class="isShort ? 'myCropper-preview-short' : 'myCropper-preview-long'">
 <div class="myCropper-preview-1 avatar-preview">
 ![](!imgCropperData.imgUploadSrc ? '/images/thumbnail/thumbnail-img.jpg' : imgCropperData.imgUploadSrc)
 </div>
 <div class="myCropper-preview-2 avatar-preview">
 ![](!imgCropperData.imgUploadSrc ? '/images/thumbnail/thumbnail-img.jpg' : imgCropperData.imgUploadSrc)
 </div>
 <div class="myCropper-preview-3 avatar-preview">
 ![](!imgCropperData.imgUploadSrc ? '/images/thumbnail/thumbnail-img.jpg' : imgCropperData.imgUploadSrc)
 </div>
 <input id="myCropper-input" type="file" :accept="imgCropperData.accept" ref="inputer" @change="handleFile">
 <Button type="ghost" class="myCropper-btn" @click="btnClick">选择图片</Button>
 <Button type="primary" class="myCropper-btn" :loading="cropperLoading" @click="crop_ok">确认</Button>
 </div>
 </div>
</template>
<script>
 var ezjsUtil = Vue.ezjsUtil;
 import Bus from './bus/bus.js' 
 export default {
 components: { Bus },
 props: {
 imgType: {
 type: String
 },
 proportionX: {
 type: Number
 },
 proportionY: {
 type: Number
 }
 },
 data () {
 return {
 imgCropperData: {
 accept: 'image/gif, image/jpeg, image/png, image/bmp',
 maxSize: 5242880,
 file: null, //上传的文件
 imgSrc: '', //读取的img文件base64数据流
 imgUploadSrc: '', //裁剪之后的img文件base64数据流
 },
 imgObj: null,
 hasSelectImg: false,
 cropperLoading: false,
 isShort: false,
 }
 },
 created: function () {
 let _this = this;
 },
 mounted: function () {
 let _this = this;
 // 初始化预览区域
 let maxWidthNum = Math.floor(300 / _this.proportionX);
 let previewWidth = maxWidthNum * _this.proportionX;
 let previewHeight = maxWidthNum * _this.proportionY;
 if (previewWidth / previewHeight <= 1.7) {
 previewWidth = previewWidth / 2;
 previewHeight = previewHeight / 2;
 _this.isShort = true;
 }
 // 设置最大预览容器的宽高
 $('.myCropper-preview-1').css('width', previewWidth + 'px');
 $('.myCropper-preview-1').css('height', previewHeight + 'px');
 // 设置中等预览容器的宽高
 $('.myCropper-container .myCropper-preview .myCropper-preview-2').css('width',( previewWidth / 2) + 'px');
 $('.myCropper-container .myCropper-preview .myCropper-preview-2').css('height', (previewHeight / 2) + 'px');
 // 设置最小预览容器的宽高
 $('.myCropper-container .myCropper-preview .myCropper-preview-3').css('width',( previewWidth / 4) + 'px');
 $('.myCropper-container .myCropper-preview .myCropper-preview-3').css('height', (previewHeight / 4) + 'px');
 },
 methods: {
 // 点击选择图片
 btnClick () {
 let _this = this;
 // 模拟input点击选择文件
 document.getElementById('myCropper-input').click();
 },
 // 选择之后的回调
 handleFile (e) {
 let _this = this;
 let inputDOM = this.$refs.inputer;
 // 通过DOM取文件数据
 _this.file = inputDOM.files[0];
 // 判断文件格式
 if (_this.imgCropperData.accept.indexOf(_this.file.type) == -1) {
 _this.$Modal.error({
 title: '格式错误',
 content: '您选择的图片格式不正确！'
 });
 return;
 }
 // 判断文件大小限制
 if (_this.file.size > 5242880) {
 _this.$Modal.error({
 title: '超出限制',
 content: '您选择的图片过大，请选择5MB以内的图片！'
 });
 return;
 }
 var reader = new FileReader();
 // 将图片将转成 base64 格式
 reader.readAsDataURL(_this.file);
 reader.onload = function () {
 _this.imgCropperData.imgSrc = this.result;
 _this.initCropper();
 }
 },
 // 初始化剪切
 initCropper () {
 let _this = this;
 // 初始化裁剪区域
 _this.imgObj = $('![](' + _this.imgCropperData.imgSrc + ')');
 let $avatarPreview = $('.avatar-preview');
 $('#myCropper-workspace').empty().html(_this.imgObj);
 _this.imgObj.cropper({
 aspectRatio: _this.proportionX / _this.proportionY,
 preview: $avatarPreview,
 crop: function(e) {
 }
 });
 _this.hasSelectImg = true;
 },
 // 确认
 crop_ok () {
 let _this = this, imgToken = null, imgBase64Data = null;
 // 判断是否选择图片
 if (_this.hasSelectImg == false) {
 _this.$Modal.error({
 title: '裁剪失败',
 content: '请选择图片，然后进行裁剪操作！'
 });
 return false;
 }
 // 确认按钮不可用
 _this.cropperLoading = true;
 let $imgData = _this.imgObj.cropper('getCroppedCanvas')
 imgBase64Data = $imgData.toDataURL('image/png'); 
 // 构造上传图片的数据
 let formData = new FormData();
 // 截取字符串
 let photoType = imgBase64Data.substring(imgBase64Data.indexOf(",") + 1);
 //进制转换
 const b64toBlob = (b64Data, contentType = '', sliceSize = 512) => {
 const byteCharacters = atob(b64Data);
 const byteArrays = [];
 for(let offset = 0; offset < byteCharacters.length; offset += sliceSize) {
 const slice = byteCharacters.slice(offset, offset + sliceSize);
 const byteNumbers = new Array(slice.length);
 for(let i = 0; i < slice.length; i++) {
 byteNumbers[i] = slice.charCodeAt(i);
 }
 const byteArray = new Uint8Array(byteNumbers);
 byteArrays.push(byteArray);
 }
 const blob = new Blob(byteArrays, {
 type: contentType
 });
 return blob;
 }
 const contentType = 'image/jepg';
 const b64Data2 = photoType;
 const blob = b64toBlob(b64Data2, contentType);
 formData.append("file", blob, "client-camera-photo.png")
 formData.append("type", _this.imgType)
 // ajax上传
 $.ajax({
 url: _this.$nfs.uploadUrl,
 method: 'POST',
 data: formData,
 // 默认为true，设为false后直到ajax请求结束(调完回掉函数)后才会执行$.ajax(...)后面的代码
 async: false,
 // 下面三个，因为直接使用FormData作为数据，contentType会自动设置，也不需要jquery做进一步的数据处理(序列化)。
 cache: false,
 contentType: false,
 processData: false,
 type: _this.imgType,
 success: function(res) {
 let imgToken = res.data.token;
 _this.cropperLoading = false;
 // 传参
 Bus.$emit('getTarget', imgToken); 
 },
 error: function(error) {
 _this.cropperLoading = false;
 _this.$Modal.error({
 title: '系统错误',
 content: '请重新裁剪图片进行上传！'
 });
 }
 });
 },
 }
 }
</script>
<style lang="less" scoped>
 .myCropper-container {
 height: 400px;
 }
 .myCropper-container #myCropper-input {
 width: 0px;
 height: 0px;
 }
 .myCropper-container #myCropper-workspace {
 width: 500px;
 height: 400px;
 border: 1px solid #dddee1;
 float: left;
 }
 // 裁剪图片未选择图片的提示文字
 .myCropper-container #myCropper-workspace .myCropper-words{
 text-align: center;
 font-size: 18px;
 padding-top: 180px;
 }
 // 裁剪图片的预览区域
 .myCropper-container .myCropper-preview-long {
 width: 300px;
 }
 .myCropper-container .myCropper-preview-short {
 width: 200px;
 }
 .myCropper-container .myCropper-preview {
 float: left;
 height: 400px;
 margin-left: 10px;
 }
 .myCropper-container .myCropper-preview .myCropper-preview-1 {
 border-radius: 5px;
 overflow: hidden;
 border: 1px solid #dddee1;
 box-shadow: 3px 3px 3px #dddee1;
 img {
 width: 100%;
 height: 100%;
 }
 }
 .myCropper-container .myCropper-preview .myCropper-preview-2 {
 margin-top: 20px;
 border-radius: 5px;
 overflow: hidden;
 border: 1px solid #dddee1;
 box-shadow: 3px 3px 3px #dddee1;
 img {
 width: 100%;
 height: 100%;
 }
 }
 .myCropper-container .myCropper-preview .myCropper-preview-3 {
 margin-top: 20px;
 border-radius: 5px;
 overflow: hidden;
 border: 1px solid #dddee1;
 box-shadow: 3px 3px 3px #dddee1;
 img {
 width: 100%;
 height: 100%;
 }
 }
 // 按钮
 .myCropper-btn {
 float: left;
 margin-top: 20px;
 margin-right: 10px;
 }
</style>

BY-LucaLJX

github: lucaljx

总结

以上所述是小编给大家介绍的基于cropper.js封装vue实现在线图片裁剪组件功能，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脚本之家网站的支持！