vue.js3:拖动旋转div(vue@3.2.37)

一，js代码:

<template>
<div style="width:100%;height:100vh;" @mousemove="onRotate" @mouseup="onUp">
  <div ref="target" style="width:300px;height:100px;position: relative;" >
    <div style="width:100%;height:100%;background: #ff0000;color:white;font-size:40px;">
      测试旋转
    </div>
    <!-- 旋转按钮 -->
    <div class="u-rotate flex-center" @mousedown="onDown" >
      <i class="iconfont icon-loading_flat"></i>
    </div>
  </div>
</div>
</template>

<script>
import {ref} from "vue";
export default {
  name: "MoveRotate",
  setup() {

    //要旋转的目标
    const target = ref(null);

    //开始时的位置
    const centerX = ref(0);
    const centerY = ref(0);
    //当时是否在拖动鼠标
    let isDrag = false;

    //鼠标按下时
    const onDown = (e) => {
      console.log(e);
      centerX.value = 158;
      centerY.value = 110;
      isDrag = true;
    }

    //鼠标移动时
    const onRotate = (e) => {
        if (isDrag == false) {
          return;
        }
        //旋转div
      let style = target.value.style;

      // 当前的鼠标坐标
      const x1 = e.clientX;
      const y1 = e.clientY;
      //三角函数
      let deg = getRotate(x1,y1);
      //console.log("deg:"+deg);
      style.transform = `rotate(${deg}deg)`;
    }
    
    // 获取旋转角度
    const getRotate = (pointX,pointY) => {
      if (pointX === centerX.value) {
        return pointY >= centerY.value ? 0 : 180
      }
      if (pointY === centerY.value) {
        return pointX < centerX.value ? 90 : 270
      }
      const x = pointX - centerX.value
      const y = pointY - centerY.value
      let angle = (Math.atan(Math.abs(x / y)) / Math.PI) * 180
      // 默认从第三象限(x<0 && y>0)开始为正
      if (x < 0 && y < 0) {
        // 第二象限
        angle = 180 - angle
      } else if (x > 0 && y < 0) {
        // 第一象限
        angle += 180
      } else if (x > 0 && y > 0) {
        // 第四象限
        angle = 360 - angle
      }
      let angleRange = 5;
      return [0, 90, 180, 270, 360, angle].find(deg => Math.abs(angle - deg) < angleRange)
    }
    
    //鼠标松开时
    const onUp = () => {
      isDrag = false;
    }

    return {
      target,
      onRotate,
      onDown,
      onUp,
    }
  }
}
</script>

<style scoped>
.u-rotate {
  position: absolute;
  z-index: 2;
  width: 24px;
  height: 24px;
  line-height: 24px;
  border-radius: 50%;
  background-image: url("data:image/svg+xml;charset=utf-8,%3Csvg width='24' height='24' xmlns='http://www.w3.org/2000/svg' fill='%23757575'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Ccircle stroke='%23CCD1DA' fill='%23FFF' cx='12' cy='12' r='11.5'/%3E%3Cpath d='M16.242 12.012a4.25 4.25 0 00-5.944-4.158L9.696 6.48a5.75 5.75 0 018.048 5.532h1.263l-2.01 3.002-2.008-3.002h1.253zm-8.484-.004a4.25 4.25 0 005.943 3.638l.6 1.375a5.75 5.75 0 01-8.046-5.013H5.023L7.02 9.004l1.997 3.004h-1.26z' fill='%23000' fill-rule='nonzero'/%3E%3C/g%3E%3C/svg%3E");
  left: 50%;
  bottom: -34px;
  transform: translateX(-50%);
  cursor: grabbing;
}
</style>

说明：刘宏缔的架构森林是一个专注架构的博客，地址：https://www.cnblogs.com/architectforest

         对应的源码可以访问这里获取： https://github.com/liuhongdi/
         或: https://gitee.com/liuhongdi

说明：作者:刘宏缔 邮箱: 371125307@qq.com

二，测试效果

三，查看vue框架的版本:

liuhongdi@lhdpc:/data/vue/pdf/image2pdf$ npm list vue
child@0.1.0 /data/vue/pdf/image2pdf
├─┬ @vue/cli-plugin-babel@5.0.6
│ └─┬ @vue/babel-preset-app@5.0.6
│   └── vue@3.2.37 deduped
└─┬ vue@3.2.37
  └─┬ @vue/server-renderer@3.2.37
    └── vue@3.2.37 deduped

标签：vue,angle,37,value,3.2,const,fill,deg
来源： https://www.cnblogs.com/architectforest/p/16624660.html