效果图

代码如下

<template>
	<view class="container" v-show="isShow">
		<view>
			<view class="cropper-content">
				<view v-if="isShowImg" class="uni-corpper"
					:style="'width:' + cropperInitW + 'px;height:' + cropperInitH + 'px;background:#000'">
					<view class="uni-corpper-content" :style="
							'width:' +
								cropperW +
								'px;height:' +
								cropperH +
								'px;left:' +
								cropperL +
								'px;top:' +
								cropperT +
								'px'
						">
						<image :src="imageSrc" :style="'width:' + cropperW + 'px;height:' + cropperH + 'px'"></image>
						<view class="uni-corpper-crop-box" @touchstart.stop="contentStartMove"
							@touchmove.stop="contentMoveing" @touchend.stop="contentTouchEnd" :style="
								'left:' + cutL + 'px;top:' + cutT + 'px;right:' + cutR + 'px;bottom:' + cutB + 'px'
							">
							<view class="uni-cropper-view-box">
								<view class="uni-cropper-dashed-h"></view>
								<view class="uni-cropper-dashed-v"></view>

								<!-- 截图区域顶部 -->
								<view class="uni-cropper-line-t" data-drag="top" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>

								<!-- 截图区域右侧 -->
								<view class="uni-cropper-line-r" data-drag="right" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>

								<!-- 截图区域底部 -->
								<view class="uni-cropper-line-b" data-drag="bottom" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>

								<!-- 截图区域左侧 -->
								<view class="uni-cropper-line-l" data-drag="left" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>

								<!-- 右下角截图滑块 -->
								<view class="uni-cropper-point point-t" data-drag="top" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-point point-tr" data-drag="topTight"></view>
								<view class="uni-cropper-point point-r" data-drag="right" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-point point-rb" data-drag="rightBottom"
									@touchstart.stop="dragStart" @touchmove.stop="dragMove"></view>
								<view class="uni-cropper-point point-b" data-drag="bottom" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove" @touchend.stop="dragEnd"></view>
								<view class="uni-cropper-point point-bl" data-drag="bottomLeft"></view>
								<view class="uni-cropper-point point-l" data-drag="left" @touchstart.stop="dragStart"
									@touchmove.stop="dragMove"></view>
								<view class="uni-cropper-point point-lt" data-drag="leftTop"></view>
							</view>
						</view>
					</view>
				</view>
			</view>
			<view class="cropper-config">
				<view class="tips">{{msg}}</view>
				<view class="button-box">
					<view class="btn">
						<img @tap="chooseImage" src="https://imgbos.ai.hanyastar.cn/stu/photo/photo_white.png"
							style="height: 44rpx;height: 37rpx;">
					</view>
					<!-- <button type="warn" @click="chooseImage">重选</button> -->
					<view class="finish-photo btn" style="">
						<img @tap="finish" class="ok-img" src="https://imgbos.ai.hanyastar.cn/stu/photo/ok.png" />
					</view>
					<!-- <text class="btn" style="color: #FFF;line-height: 142rpx;text-align: right;" @click="rotateImgTap">旋转</text> -->
					<view class="btn" style="">
						<img @tap="rotateImgTap" src="https://imgbos.ai.hanyastar.cn/stu/photo/rotate.png"
							style="height: 44rpx;height: 37rpx;" />
					</view>
					<!-- <text class="btn" style="color: #FFF;line-height: 142rpx;text-align: right;" @click="previewImg">预览</text> -->
					<!-- <button type="warn" @click="finish">完成</button> -->
				</view>
			</view>
			<canvas canvas-id="myCanvas" :style="
					'position:absolute;border: 2px solid red; width:' +
						imageW +
						'px;height:' +
						imageH +
						'px;top:-9999px;left:-9999px;'
				"></canvas>
		</view>
	</view>
</template>

<script>
	let sysInfo = uni.getSystemInfoSync();
	let SCREEN_WIDTH = sysInfo.screenWidth;
	let SCREEN_HEIGHT = sysInfo.windowHeight;
	let PAGE_X, // 手按下的x位置
		PAGE_Y, // 手按下y的位置
		PR = sysInfo.pixelRatio, // dpi
		T_PAGE_X, // 手移动的时候x的位置
		T_PAGE_Y, // 手移动的时候Y的位置
		CUT_L, // 初始化拖拽元素的left值
		CUT_T, // 初始化拖拽元素的top值
		CUT_R, // 初始化拖拽元素的
		CUT_B, // 初始化拖拽元素的
		CUT_W, // 初始化拖拽元素的宽度
		CUT_H, //  初始化拖拽元素的高度
		IMG_RATIO, // 图片比例
		IMG_REAL_W, // 图片实际的宽度
		IMG_REAL_H, // 图片实际的高度
		DRAFG_MOVE_RATIO = 1, //移动时候的比例,
		INIT_DRAG_POSITION = 100, // 初始化屏幕宽度和裁剪区域的宽度之差,用于设置初始化裁剪的宽度
		DRAW_IMAGE_W = sysInfo.screenWidth; // 设置生成的图片宽度
	export default {
		/**
		 * 页面的初始数据
		 */
		data() {
			return {
				originImg: '',
				rotateTime: 1, // 旋转次数
				imageSrc: "",
				isShow: false,
				isShowImg: false,
				// 初始化的宽高
				cropperInitW: SCREEN_WIDTH,
				cropperInitH: SCREEN_HEIGHT,
				// 动态的宽高
				cropperW: SCREEN_WIDTH,
				cropperH: SCREEN_HEIGHT - 100,
				// 动态的left top值
				cropperL: 0,
				cropperT: 0,
				transL: 0,
				transT: 0,
				// 图片缩放值
				scaleP: 0,
				imageW: 0,
				imageH: 0,
				// 裁剪框 宽高
				cutL: 0,
				cutT: 0,
				cutB: SCREEN_WIDTH,
				cutR: "100%",
				qualityWidth: DRAW_IMAGE_W,
				innerAspectRadio: DRAFG_MOVE_RATIO,
			};
		},
		props: {
			/* 截图质量,压缩比  */
			quality: {
				type: Number | String,
				default: 1,
			},
			msg: {
				type: String,
				default: '一次只选一题,更容易搜到答案'
			},

			/*
			 * 传入图片路径,将跳过选择图片步骤直接进入截图界面。
			 * 需要特别注意:H5端 Canvas 内绘制的图像需要支持跨域访问才能成功。
			 */
			imgSrc: String,

			/* 输出图片类型:仅支持png格式或jpg格式  */
			fileType: {
				type: String,
				default: "png",
				validator: function(t) {
					// 这个值必须匹配下列字符串中的一个
					return t === "png" || t === "jpg";
				},
			},

			/* 截取类型,自由截取free;固定比例截取(正方形)fixed  */
			cropperType: {
				type: String,
				default: "free",
				validator: function(t) {
					// 这个值必须匹配下列字符串中的一个
					return t === "free" || t === "fixed" || t === "ratio";
				},
			},
			ratio: {
				type: Number,
				default: 1,
			},
		},
		created() {},

		onLoad(opt) {},
		mounted() {
			if (this.imgSrc) {
				this.imageSrc = this.imgSrc;
				this.originImg = this.imgSrc;
				console.log(this.imgSrc, "imgSrc");
				console.log(this.cropperType, "cropperType");
				this.loadImage();
				this.isShow = true;
				this.isShowImg = true;
			}
		},
		methods: {
			//1中使用到的将blob转化为file方法 和图片的压缩方法
			objectURLToBlob(url, callback) {
				var http = new XMLHttpRequest();
				http.open('GET', url, true);
				http.responseType = 'blob';
				http.onload = function(e) {
					if (this.status == 200 || this.status === 0) {
						callback(this.response);
					}
				};
				http.send();
			},
			async comprossImage(imgSrc, maxWidth, func) {
				if (!imgSrc) return 0;
				return new Promise((resolve, reject) => {
					uni.getImageInfo({
						src: imgSrc,
						success(res) {
							let img = new Image();
							img.src = res.path;
							console.log(img);

							let canvas = document.createElement('canvas');

							let obj = new Object();
							obj.img = img;
							obj.canvas = canvas;
							resolve(func(obj));
						}
					});
				});
			},
			rotateImg(img, direction, canvas, times = 1) {
				console.log('开始旋转');
				//最小与最大旋转方向,图片旋转4次后回到原方向
				var min_step = 0;
				var max_step = 3;
				if (img == null) return;

				//img的高度和宽度不能在img元素隐藏后获取,否则会出错
				var height = img.height;
				var width = img.width;
				let maxWidth = 500;
				let canvasWidth = width; //图片原始长宽
				let canvasHeight = height;
				let base = canvasWidth / canvasHeight;

				width = canvasWidth;
				height = canvasHeight;
				var step = 0;

				if (step == null) {
					step = min_step;
				}

				if (direction == 'right') {
					step += times;
					//旋转到原位置,即超过最大值
					step > max_step && (step = min_step);
				} else if (direction == 'left') {
					step -= times;
					step < min_step && (step = max_step);
				} else {
					//不旋转
					step = 0;
				}

				//旋转角度以弧度值为参数
				var degree = (step * 90 * Math.PI) / 180;
				var ctx = canvas.getContext('2d');
				// console.log(degree)
				// console.log(step)
				switch (step) {
					case 1:
						console.log('右旋转 90度');
						canvas.width = height;
						canvas.height = width;
						ctx.rotate(degree);
						ctx.drawImage(img, 0, -height, width, height);
						break;
					case 2:
						//console.log('旋转 180度')
						canvas.width = width;
						canvas.height = height;
						ctx.rotate(degree);
						ctx.drawImage(img, -width, -height, width, height);
						break;
					case 3:
						console.log('左旋转 90度');
						canvas.width = height;
						canvas.height = width;
						ctx.rotate(degree);
						ctx.drawImage(img, -width, 0, width, height);
						break;
					default:
						//不旋转
						canvas.width = width;
						canvas.height = height;
						ctx.drawImage(img, 0, 0, width, height);
						break;
				}

				let baseStr = canvas.toDataURL('image/jpeg', 1);
				// console.log(baseStr)
				// return baseStr;
				// replace("data:image/jpeg;base64,", "")
				// 将base64转化为blob文件进行图片上传,(考虑到转化后再上传耗费时间暂时没有使用,如果需要base64ToPath 方法可百度或者私信我)
				// base64ToPath(baseStr).then(tempPath => {
				// 	this.uploadBgImg(tempPath)
				// });
				// 自定义上传请求
				//this.uploadBaseImg(baseStr);
				return baseStr
			},
			// 旋转图片
			async rotateImgTap() {
				// #ifdef H5
				var img = null;
				var canvas = null;
				await this.comprossImage(this.imageSrc, 50000, function(e) {
					img = e.img;
					canvas = e.canvas;
				});
				let src = this.rotateImg(img, 'right', canvas, this.rotateTime);

				if (this.rotateTime == 4) {
					this.rotateTime = 1
				} else {
					this.rotateTime = this.rotateTime + 1
				}
				console.info(this.rotateTime)
				this.setData({
					imageSrc: src,
				});
				this.loadImage();
				this.isShow = true;
				// #endif
				// #ifdef APP-PLUS
				var img = {};
				var _this = this
				if(this.rotateTime == 1) {
					uni.showLoading({
						title: "图片旋转中...",
					});
					plus.zip.compressImage({
					                src: this.originImg,
					                dst: "_doc/uniapp_temp" + '/compressed/' + Math.round(new Date()) + '.png',
					                format: 'png',
					                quality: 80,
					                width: 'auto',
					                height: 'auto',
					                rotate: 90,
					            },
					            function(event) {
									console.info(event.target)
									_this.setData({
										imageSrc: event.target
									});
									_this.loadImage();
									_this.isShow = true;
									uni.hideLoading();
					            },
					            function(error) {
									uni.hideLoading();
									uni.showToast({
										title: "图片不支持旋转!",
										icon: "none",
									});
					            })

					//this.rotate(this.originImg)
				} else {
					_this.setData({
						imageSrc: this.originImg,
					});
					_this.loadImage();
					_this.isShow = true;
				}
				
				if (this.rotateTime == 2) {
					this.rotateTime = 1
				} else {
					this.rotateTime = this.rotateTime + 1
				}
				console.info(this.rotateTime)
				// #endif
			},
			
			rotate(tempFilePaths) {
				const that = this
				var _this = this;
				uni.getImageInfo({
					// 获取图片的信息
					src: tempFilePaths,
					success: (res1) => {
						console.log(res1)
						// 将canvas1的内容复制到canvas2中
						let canvasContext = uni.createCanvasContext('myCanvas', this)
						let rate = res1.height / res1.width
						let width = 375 / rate
						let height = 375
						canvasContext.translate(0, 0)
						canvasContext.rotate((90 * Math.PI) / 180)
						canvasContext.drawImage(tempFilePaths, 0, -999, width, 999)
						canvasContext.draw(true, (data) => {
							// 将之前在绘图上下文中的描述(路径、变形、样式)画到 canvas 中
							uni.canvasToTempFilePath({
								// 把当前画布指定区域的内容导出生成指定大小的图片。在 draw() 回调里调用该方法才能保证图片导出成功。
								x:0,
								y:0,
								canvasId: 'myCanvas',
								fileType: 'png',
								width:375,
								
								quality: 1, //图片质量
								success(res2) {
									// 调用uni.uploadFile上传图片即可
									console.log(res2.tempFilePath)
									_this.setData({
										imageSrc: res2.tempFilePath,
									});
									_this.loadImage();
									_this.isShow = true;
								}
							}, _this)

						});
					}
				})
			},
			setData: function(obj) {
				let that = this;
				Object.keys(obj).forEach(function(key) {
					that.$set(that.$data, key, obj[key]);
				});
			},

			/* 选择图片  */
			chooseImage: function(e) {
				console.info('点击了')
				var _this = this;
				uni.chooseImage({
					count: 1,
					success: function(res) {
						//#ifndef H5
						let index = res.tempFilePaths[0].lastIndexOf(".");
						let imgUrl = res.tempFilePaths[0].substr(index + 1);

						if (imgUrl != "png" && imgUrl != "jpg" && imgUrl != "jpeg") {
							uni.$u.toast('请上传jpg、jpeg、png类型的图片');
							return
						}
						//#endif
						//#ifdef H5
						if (res.tempFiles[0].type !== 'image/jpeg' && res.tempFiles[0].type !==
							'image/png' && res.tempFiles[0].type !== 'image/jpeg') {
							uni.$u.toast('请上传jpg、jpeg、png类型的图片');
							return
						}
						//#endif
						if (res.tempFiles[0].size / 1024 < 1024 * 1024 * 20) {
							_this.originImg = res.tempFilePaths[0]
							_this.setData({
								imageSrc: res.tempFilePaths[0],
							});
							_this.loadImage();
							_this.isShow = true;
						} else {
							uni.showToast({
								title: '图片大小不能超过20M,当前大小' + (res.tempFiles[0].size / 1024).toFixed(
									2) + 'KB',
								icon: 'none'
							})
						}
					},
				});
			},
			/* 将图片加载到画布  */
			loadImage: function() {
				var _this = this;
				uni.showLoading({
					title: "图片加载中...",
				});

				/* 获取图片信息  */
				uni.getImageInfo({
					src: _this.imageSrc,
					success: function success(res) {
						let imgH = res.height;
						let imgW = res.width;

						// let IMG_SCR_H_R = SCREEN_HEIGHT / imgH;
						// let IMG_SCR_W_R = SCREEN_WIDTH / imgW;

						/* 图片的宽高比  */
						IMG_RATIO = imgW / imgH;

						/**
						 * 如果图片更高一些,为确保图片能够完整在视窗内显示需如下处理
						 * 1. 缩放图片的高为 视窗高度减去底部菜单按钮高度(120)
						 * 2. 根据图片缩放后的高度,根据图片宽高比计算图片的宽度
						 * 3. 如果步骤2计算的图片宽度大于屏幕宽度,则需要再次调整图片宽度为视窗宽度-margin(10)
						 * 4. 根据步骤3的宽度,结合图片宽高比重新计算图片的高度
						 */
						if (IMG_RATIO < 1 && (SCREEN_HEIGHT - 133) * IMG_RATIO < SCREEN_WIDTH - 10) {
							IMG_REAL_W = (SCREEN_HEIGHT - 133) * IMG_RATIO;
							IMG_REAL_H = SCREEN_HEIGHT - 133;
						} else {
							IMG_REAL_W = SCREEN_WIDTH - 10;
							IMG_REAL_H = IMG_REAL_W / IMG_RATIO;
						}

						console.log("ratio", "=====1====");
						/* 初始化裁剪区域的位置和形状  */
						let [cutT, cutB, cutL, cutR] = _this.initCutArea(IMG_RATIO, IMG_REAL_H,
							IMG_REAL_W);

						_this.setData({
							/* 裁剪区域的宽高同图片尺寸  */
							cropperW: IMG_REAL_W,
							cropperH: IMG_REAL_H,

							/* 上下左右各留一定的margin已便更好的拖动裁剪区域  */
							cropperL: Math.ceil((SCREEN_WIDTH - IMG_REAL_W) / 2),

							/* 留出底部操作按钮位置 70  */
							cropperT: uni.getStorageSync("navHeight"),
							cutL: cutL,
							cutT: cutT,
							cutR: cutR,
							cutB: cutB,
							// 图片缩放值
							imageW: IMG_REAL_W,
							imageH: IMG_REAL_H,
							scaleP: IMG_REAL_W / SCREEN_WIDTH,
							qualityWidth: DRAW_IMAGE_W,
							innerAspectRadio: IMG_RATIO,
						});
						_this.setData({
							isShowImg: true,
						});
						uni.hideLoading();
					},
				});
			},

			initCutArea(IMG_RATIO, IMG_REAL_H, IMG_REAL_W) {
				let _this = this;
				/* 自由裁剪裁剪区域默认覆盖整个图片  */
				let cutT = 0;
				let cutB = 0;
				let cutL = 0;
				let cutR = 0;
				console.log("ratio", "=====2====" + this.cropperType);
				/* 正方形裁剪,初始化裁剪区域为正方形并居中  */
				if (_this.cropperType == "fixed") {
					// if (IMG_RATIO < 1) {
					// 	/* 图片比较高  */
					// 	cutT = (IMG_REAL_H - IMG_REAL_W) / 2;
					// 	cutB = (IMG_REAL_H - IMG_REAL_W) / 2;
					// } else {
					// 	/* 图片比较宽  */
					// 	cutL = (IMG_REAL_W - IMG_REAL_H) / 2;
					// 	cutR = (IMG_REAL_W - IMG_REAL_H) / 2;
					// }

					if (IMG_RATIO < 1) {
						/* 图片比较高  */
						cutT = (IMG_REAL_H - IMG_REAL_W) / 2;
						cutB = (IMG_REAL_H - IMG_REAL_W) / 2;
					} else {
						/* 图片比较宽  */
						cutL = (IMG_REAL_W - IMG_REAL_H) / 2;
						cutR = (IMG_REAL_W - IMG_REAL_H) / 2;
					}
				}

				/* 固定比例裁剪,初始化裁剪区域比例和设定值相同  */
				if (_this.cropperType == "ratio") {
					let ratio = +_this.ratio;
					console.log("ratio", "1111")
					if (IMG_RATIO < 1) {
						console.log("ratio", "1111112222")
						/* 图片比较高  */
						if (IMG_REAL_W / ratio > IMG_REAL_H) {
							cutT = cutB = 0;
							cutL = cutR = (IMG_REAL_W - IMG_REAL_H * ratio) / 2;
						} else {
							cutR = cutL = 0;
							cutT = cutB = (IMG_REAL_H - IMG_REAL_W / ratio) / 2;
						}
						// cutR = cutL = 0;
						// cutT = cutB= (IMG_REAL_H - IMG_REAL_W/5*3)/2
					} else {
						console.log("ratio", "111111333")
						/* 图片比较宽  */
						if (IMG_REAL_H * ratio > IMG_REAL_W) {
							cutL = cutR = 0;
							cutB = cutT = (IMG_REAL_H - IMG_REAL_W / ratio) / 2;
						} else {
							cutT = cutB = 0;
							cutL = cutR = (IMG_REAL_W - IMG_REAL_H * ratio) / 2;
						}
					}
				}
				console.info(cutT, cutB, cutL, cutR)
				return [cutT, cutB, cutL, cutR];
			},
			// 拖动时候触发的touchStart事件
			contentStartMove(e) {
				PAGE_X = e.touches[0].pageX;
				PAGE_Y = e.touches[0].pageY;
			},
			// 拖动时候触发的touchMove事件
			contentMoveing(e) {
				var _this = this;
				var dragLengthX = (PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO;
				var dragLengthY = (PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO;
				// 左移
				if (dragLengthX > 0) {
					//向左移动,剪裁区域超过了当前图片的左边,判定移动距离,为初始裁剪区域距离左边距
					if (this.cutL - dragLengthX < 0) dragLengthX = this.cutL;
				} else {
					//向右移动,剪裁区域超过了当前图片的右边,判定移动距离,为初始裁剪区域距离右边距
					if (this.cutR + dragLengthX < 0) dragLengthX = -this.cutR;
				}
				if (dragLengthY > 0) {
					//向上移动,剪裁区域超过了当前图片的上边,判定移动距离,为初始裁剪区域距离顶部边距
					if (this.cutT - dragLengthY < 0) dragLengthY = this.cutT;
				} else {
					//向下移动,剪裁区域超过了当前图片的底部,判定移动距离,为初始裁剪区域距离底部边距
					if (this.cutB + dragLengthY < 0) dragLengthY = -this.cutB;
				}
				this.setData({
					cutL: this.cutL - dragLengthX,
					cutT: this.cutT - dragLengthY,
					cutR: this.cutR + dragLengthX,
					cutB: this.cutB + dragLengthY,
				});
				PAGE_X = e.touches[0].pageX;
				PAGE_Y = e.touches[0].pageY;
			},
			contentTouchEnd() {},
			transBase64() {},
			// 获取图片尺寸信息
			previewImg() {
				try {
					var _this = this;
					uni.showLoading({
						title: "图片生成中...",
					});
					// 将图片写入画布
					const ctx = uni.createCanvasContext("myCanvas", _this);
					ctx.drawImage(_this.imageSrc, 0, 0, IMG_REAL_W, IMG_REAL_H);
					ctx.draw(true, () => {
						// 获取画布要裁剪的位置和宽度   均为百分比 * 画布中图片的宽度    保证了在微信小程序中裁剪的图片模糊  位置不对的问题 canvasT = (_this.cutT / _this.cropperH) * (_this.imageH / pixelRatio)
						var canvasW = ((_this.cropperW - _this.cutL - _this.cutR) / _this.cropperW) * IMG_REAL_W;
						var canvasH = ((_this.cropperH - _this.cutT - _this.cutB) / _this.cropperH) * IMG_REAL_H;
						var canvasL = (_this.cutL / _this.cropperW) * IMG_REAL_W;
						var canvasT = (_this.cutT / _this.cropperH) * IMG_REAL_H;
						uni.canvasToTempFilePath({
								x: canvasL,
								y: canvasT,
								width: canvasW,
								height: canvasH,
								// destWidth: canvasW,
								// destHeight: canvasH,
								quality: +this.quality,
								fileType: this.fileType,
								canvasId: "myCanvas",
								success: function(res) {
									uni.hideLoading();
									// 成功获得地址的地方
									uni.previewImage({
										current: "", // 当前显示图片的http链接
										urls: [res.tempFilePath], // 需要预览的图片http链接列表
									});
								},
								fail: function(err) {
									uni.hideLoading();
									uni.showToast({
										title: "图片截取失败!",
										icon: "none",
									});
								},
							},
							_this
						);
					});
				} catch (e) {}
			},

			/* 完成裁剪,输出裁剪后的图片路径  */
			finish: function() {
				var _this = this;
				uni.showLoading({
					title: "图片生成中...",
				});
				// 将图片写入画布
				const ctx = uni.createCanvasContext("myCanvas", _this);
				ctx.drawImage(_this.imageSrc, 0, 0, IMG_REAL_W, IMG_REAL_H);
				ctx.draw(true, () => {
					// 获取画布要裁剪的位置和宽度   均为百分比 * 画布中图片的宽度    保证了在微信小程序中裁剪的图片模糊  位置不对的问题 canvasT = (_this.cutT / _this.cropperH) * (_this.imageH / pixelRatio)
					var canvasW = ((_this.cropperW - _this.cutL - _this.cutR) / _this.cropperW) * IMG_REAL_W;
					var canvasH = ((_this.cropperH - _this.cutT - _this.cutB) / _this.cropperH) * IMG_REAL_H;
					var canvasL = (_this.cutL / _this.cropperW) * IMG_REAL_W;
					var canvasT = (_this.cutT / _this.cropperH) * IMG_REAL_H;
					uni.canvasToTempFilePath({
							x: canvasL,
							y: canvasT,
							width: canvasW,
							height: canvasH,
							// destWidth: canvasW,
							// destHeight: canvasH,
							quality: +this.quality,
							fileType: this.fileType,
							canvasId: "myCanvas",
							success: function(res) {
								uni.hideLoading();
								// 成功获得地址的地方
								// #ifdef H5
								_this.$emit("getImg", res.tempFilePath);
								// #endif
								// #ifdef APP-PLUS
								plus.io.resolveLocalFileSystemURL(res.tempFilePath, function(entry) {
									entry.file(function(file) {
										console.log(file)
										var reader = new plus.io.FileReader();
										reader.readAsDataURL(file);
										reader.onloadend = function(e) {
											// console.log(e.target.result)
											const resBase64 = e.target.result
												.replace('data:audio/mpeg;base64,',
													'')
											console.log(resBase64)
											_this.$emit("getImg", resBase64);
										}
									})
								})
								// #endif
								_this.isShow = false;
							},
							fail: function(err) {
								uni.hideLoading();
								uni.showToast({
									title: "图片截取失败!",
									icon: "none",
								});
							},
						},
						_this
					);
				});
			},

			// 设置大小的时候触发的touchStart事件
			dragStart(e) {
				T_PAGE_X = e.touches[0].pageX;
				T_PAGE_Y = e.touches[0].pageY;
				CUT_L = this.cutL;
				CUT_R = this.cutR;
				CUT_B = this.cutB;
				CUT_T = this.cutT;
			},

			// 设置大小的时候触发的touchMove事件
			dragMove(e) {
				// this.cropperType == "fixed" ? this.fixedScaleDrag(e) : this.freeDrag(e);
				this[this.cropperType + "Drag"](e);
			},

			/* 固定比例(正方形)截取 ,只有右下角裁剪滑动拖动有效*/
			fixedDrag(e) {
				var _this = this;
				var dragType = e.target.dataset.drag;
				switch (dragType) {
					case "rightBottom":
						var dragLengthX = (T_PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO;
						// var dragLengthY = (T_PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO;
						// if (CUT_B + dragLengthY < 0) dragLengthY = -CUT_B;

						if (CUT_R + dragLengthX < 0) dragLengthX = -CUT_R;

						/* 右侧和底部同比变化 */
						let cutB = CUT_B + dragLengthX;
						let cutR = CUT_R + dragLengthX;

						/* 越界判断  */
						if (_this.cutB == 0 && cutB < 0) return;
						if (_this.cutR == 0 && cutR < 0) return;

						(_this.cutB > 0 || CUT_B == 0) &&
						this.setData({
							cutB: cutB < 0 ? 0 : cutB,
							cutR: cutR,
						});
						break;
					default:
						break;
				}
			},

			/* 等比例截图,只能通过右下角的滑块改变截图区域  */
			ratioDrag(e) {
				var _this = this;
				var dragType = e.target.dataset.drag;
				switch (dragType) {
					case "rightBottom":
						var dragLengthX = (T_PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO;
						// var dragLengthY = (T_PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO;
						// if (CUT_B + dragLengthY < 0) dragLengthY = -CUT_B;

						if (CUT_R + dragLengthX < 0) dragLengthX = -CUT_R;

						/* 右侧和底部同比变化 */
						let cutB = CUT_B + dragLengthX / _this.ratio;
						let cutR = CUT_R + dragLengthX;

						/* 越界判断  */
						if (_this.cutB == 0 && cutB < 0) return;
						if (_this.cutR == 0 && cutR < 0) return;

						(_this.cutB > 0 || CUT_B == 0) &&
						this.setData({
							cutB: cutB < 0 ? 0 : cutB,
							cutR: cutR,
						});
						break;
					default:
						break;
				}
			},

			/* 自由截取,整个裁剪边框均能拖动  */
			freeDrag(e) {
				var _this = this;
				var dragType = e.target.dataset.drag;
				switch (dragType) {
					case "right":
						var dragLength = (T_PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO;
						if (CUT_R + dragLength < 0) dragLength = -CUT_R;
						this.setData({
							cutR: CUT_R + dragLength,
						});
						break;
					case "left":
						var dragLength = (T_PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO;
						if (CUT_L - dragLength < 0) dragLength = CUT_L;
						if (CUT_L - dragLength > this.cropperW - this.cutR)
							dragLength = CUT_L - (this.cropperW - this.cutR);
						this.setData({
							cutL: CUT_L - dragLength,
						});
						break;
					case "top":
						var dragLength = (T_PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO;
						if (CUT_T - dragLength < 0) dragLength = CUT_T;
						if (CUT_T - dragLength > this.cropperH - this.cutB)
							dragLength = CUT_T - (this.cropperH - this.cutB);
						this.setData({
							cutT: CUT_T - dragLength,
						});
						break;
					case "bottom":
						var dragLength = (T_PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO;
						if (CUT_B + dragLength < 0) dragLength = -CUT_B;
						this.setData({
							cutB: CUT_B + dragLength,
						});
						break;
					case "rightBottom":
						var dragLengthX = (T_PAGE_X - e.touches[0].pageX) * DRAFG_MOVE_RATIO;
						var dragLengthY = (T_PAGE_Y - e.touches[0].pageY) * DRAFG_MOVE_RATIO;
						if (CUT_B + dragLengthY < 0) dragLengthY = -CUT_B;
						if (CUT_R + dragLengthX < 0) dragLengthX = -CUT_R;
						let cutB = CUT_B + dragLengthY;
						let cutR = CUT_R + dragLengthX;
						this.setData({
							cutB: cutB,
							cutR: cutR,
						});
						break;
					default:
						break;
				}
			},
		},
	};
</script>

<style lang="scss" scoped>
	/* pages/uni-cropper/index.wxss */
	.container {
		background-color: #fff;
		position: fixed;
		top: 0;
		left: 0;
		right: 0;
		bottom: 50px;
		display: block;
		align-items: center;
		flex-direction: column;
		z-index: 998;
		height: 100vh;
	}

	.cropper-config {
		position: fixed;
		z-index: 1;
		bottom: 10px;
		left: 0;
		right: 0;

		width: 100%;
		padding: 0rpx 120rpx;
		box-sizing: border-box;
		margin: 0 auto;

		/* padding: 20upx 40upx; */
		.tips {
			height: 42rpx;
			font-size: 30rpx;
			color: #FFFFFF;
			text-align: center;
			z-index: 1;
		}
	}

	.button-box {
		display: flex;
		flex-direction: row;
		justify-content: space-between;
		align-items: center;
		width: 100%;

		.btn {}

		.finish-photo {
			width: 142rpx;
			height: 142rpx;
			background: #45D6DD;
			border-radius: 100%;
			display: flex;
			align-items: center;
			justify-content: center;

			.ok-img {
				width: 82rpx;
			}
		}
	}

	.button-box button {
		width: 25%;
		line-height: 35px;
		height: 35px;
	}

	.cropper-content {
		width: 100%;
		min-height: 750upx;
	}

	.uni-corpper {
		position: relative;

		overflow: hidden;

		box-sizing: border-box;
		margin: 0 auto;

		-webkit-user-select: none;
		-moz-user-select: none;
		-ms-user-select: none;
		user-select: none;

		-webkit-tap-highlight-color: transparent;
		-webkit-touch-callout: none;
	}

	.uni-corpper-content {
		position: relative;
		position: absolute;
		top: 0;
		bottom: 0;
		left: 0px !important;
		right: 0;
		margin: auto;
		max-width: 100%;
		max-height: 100%;
	}

	.uni-corpper-content image {
		display: block;

		width: 100%;
		min-width: 0 !important;
		max-width: none !important;
		/* height: 100%; */
		min-height: 0 !important;
		/* max-height: none !important; */

		max-height: calc(100vh - 100upx);
		margin: 0 auto;

		image-orientation: 0deg !important;
	}

	/* 移动图片效果 */
	.uni-cropper-drag-box {
		position: absolute;
		z-index: 1;
		top: 0;
		right: 0;
		bottom: 0;
		left: 0;

		cursor: move;

		background: #00000050;
	}

	/* 内部的信息 */
	.uni-corpper-crop-box {
		position: absolute;
		z-index: 2;
		max-height: calc(100vh - 100upx);
		background: rgba(56, 50, 50, 0.479);
	}

	.uni-corpper-crop-box .uni-cropper-view-box {
		position: relative;

		display: block;
		overflow: visible;

		width: 100%;
		height: 100%;

		max-height: calc(100vh - 100upx);
		outline: 5upx solid #646161;
		outline-color: #FFFFFF;
	}

	/* 横向虚线 */
	.uni-cropper-dashed-h {
		position: absolute;
		top: 33.33333333%;
		left: 0;

		width: 100%;
		height: 33.33333333%;
		border-top: 1upx dashed #FFFFFF50;
		border-bottom: 1upx dashed #FFFFFF50;
	}

	/* 纵向虚线 */
	.uni-cropper-dashed-v {
		position: absolute;
		top: 0;
		left: 33.33333333%;

		width: 33.33333333%;
		height: 100%;

		border-right: 1upx dashed #FFFFFF50;
		border-left: 1upx dashed #FFFFFF50;
	}

	/* 四个方向的线  为了之后的拖动事件*/
	.uni-cropper-line-t {
		position: absolute;
		top: 0;
		left: 0;

		display: block;

		width: 100%;
		height: 3upx;

		cursor: n-resize;

		opacity: 0.1;
		background-color: white;
	}

	.uni-cropper-line-t::before {
		position: absolute;
		z-index: 11;
		top: 50%;
		right: 0upx;
		bottom: 0;

		width: 100%;
		height: 41upx;

		content: "";
		-webkit-transform: translate3d(0, -50%, 0);
		transform: translate3d(0, -50%, 0);

		background: transparent;
	}

	.uni-cropper-line-r {
		position: absolute;
		top: 0;
		right: 0upx;

		display: block;

		width: 3upx;
		height: 100%;

		cursor: e-resize;

		opacity: 0.1;
		background-color: white;
	}

	.uni-cropper-line-r::before {
		position: absolute;
		z-index: 11;
		top: 0;
		bottom: 0;
		left: 50%;

		width: 41upx;
		height: 100%;

		content: "";
		-webkit-transform: translate3d(-50%, 0, 0);
		transform: translate3d(-50%, 0, 0);

		background: transparent;
	}

	.uni-cropper-line-b {
		position: absolute;
		bottom: 0;
		left: 0;

		display: block;

		width: 100%;
		height: 3upx;

		cursor: s-resize;

		opacity: 0.1;
		background-color: white;
	}

	.uni-cropper-line-b::before {
		position: absolute;
		z-index: 11;
		top: 50%;
		right: 0upx;
		bottom: 0;

		width: 100%;
		height: 41upx;

		content: "";
		-webkit-transform: translate3d(0, -50%, 0);
		transform: translate3d(0, -50%, 0);

		background: transparent;
	}

	.uni-cropper-line-l {
		position: absolute;
		top: 0;
		left: 0;

		display: block;

		width: 3upx;
		height: 100%;

		cursor: w-resize;

		opacity: 0.1;
		background-color: white;
	}

	.uni-cropper-line-l::before {
		position: absolute;
		z-index: 11;
		top: 0;
		bottom: 0;
		left: 50%;

		width: 41upx;
		height: 100%;

		content: "";
		-webkit-transform: translate3d(-50%, 0, 0);
		transform: translate3d(-50%, 0, 0);

		background: transparent;
	}

	.uni-cropper-point {
		position: absolute;
		z-index: 3;

		width: 5upx;
		height: 5upx;

		opacity: 0.75;
		background-color: rgb(145, 132, 132);
	}

	.point-t {
		top: -3upx;
		left: 50%;

		margin-left: -3upx;

		cursor: n-resize;
	}

	.point-tr {
		top: -3upx;
		left: 100%;

		margin-left: -3upx;

		cursor: n-resize;
	}

	.point-r {
		top: 50%;
		left: 100%;

		margin-top: -3upx;
		margin-left: -3upx;

		cursor: n-resize;
	}

	.point-rb {
		position: absolute;
		z-index: 1112;
		top: 100%;
		left: 100%;

		width: 36upx;
		height: 36upx;

		cursor: n-resize;
		-webkit-transform: translate3d(-50%, -50%, 0);
		transform: translate3d(-50%, -50%, 0);

		opacity: 1;
		background-color: rgb(231, 222, 222);
	}

	.point-b {
		top: 100%;
		left: 50%;

		margin-top: -3upx;
		margin-left: -3upx;

		cursor: n-resize;
	}

	.point-bl {
		top: 100%;
		left: 0;

		margin-top: -3upx;
		margin-left: -3upx;

		cursor: n-resize;
	}

	.point-l {
		top: 50%;
		left: 0;

		margin-top: -3upx;
		margin-left: -3upx;

		cursor: n-resize;
	}

	.point-lt {
		top: 0;
		left: 0;

		margin-top: -3upx;
		margin-left: -3upx;

		cursor: n-resize;
	}

	/* 裁剪框预览内容 */
	.uni-cropper-viewer {
		position: relative;

		overflow: hidden;

		width: 100%;
		height: 100%;
	}

	.uni-cropper-viewer image {
		position: absolute;
		z-index: 2;
	}
</style>

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