mousedown拖拽功能(vue3+ts)

因为项目有rem适配，使用第三方插件无法处理适配问题，所有只能自己写拖拽功能了
拖拽一般都会想到按下，移动，放开，但是本人亲测，就在div绑定一个按下事件就行了（在事件里面写另外两个事件），另外两个绑上，会莫名其妙卡死，那种莫名其妙的问题

推荐几个开发调试时使用的第三方拖动插件吧，虽然没用上，但是他们是真的好vue-drag-resize和vuedraggable，其中前者更轻量化，后者功能更全

主要功能：

效果图：

界面：（就是大的父盒子包着几个小盒子，盒子里面有图片和文字）

        <div class="range" id="range" ref="range"><divclass="iconItem"v-for="(item, index) in pointList":key="index"@mousedown.stop.prevent.native="mousedown($event, item)":style="{left: item.dx + 'px',top: item.dy + 'px','z-index': item.zIndex,}"><![e-mail]="mousemove($event, item)"@mouseup.stop.prevent.native="mouseup($event, item)"--><imgdraggable="false":src="typeList[item.type].src":alt="typeList[item.type].name + item.EName"/><span>{{ typeList[item.type].name + item.EName }}</span></div></div>

逻辑：

<script setup lang="ts">
import { ref, reactive, watch, computed, Ref } from "vue";
import { mapPunctuation } from "@/utils/youran";
let rem = ref(0.005208); // 10/1920  做好功能给上面的left top乘上去就行了 left: item.dx * rem + 'px'const range: Ref = ref(null);// 这里只是把存在文件里的base64图片文件取出来，
let typeList = reactive([{type: 1,src: "",name: "球机-摄像头",},{type: 2,src: "",name: "抢机-摄像头",},{type: 3,src: "",name: "无源打卡设备",},{type: 4,src: "",name: "无源打卡设备",},{type: 5,src: "",name: "反向控制",},
]);typeList.forEach((item, index) => {item.src = mapPunctuation[index].src;
});let pointList = ref([{fId: "111",type: 1,EId: "",EName: "",dx: 0,dy: 0,zIndex: 2,},
]);// 鼠标事件
let downType = ref(false);
let disX = 0;
let disY = 0;
let odiv: any = null;
let mousedown = (e: any, item: any) => {downType.value = true;console.log("按下事件");odiv = e.target;disX = e.clientX - odiv.offsetLeft;disY = e.clientY - odiv.offsetTop;document.onmousemove = (e) => {console.log("移动事件");//计算元素位置(需要判断临界值)let left = e.clientX - disX;let top = e.clientY - disY;let { offsetHeight: pondModelHeight, offsetWidth: pondModelWidth } =range.value;let { offsetHeight: sonNodeHeight, offsetWidth: sonNodeWidth } = odiv;// 左上角(left)if (left < 0) {left = 0;}if (top < 0) {top = 0;}// 左下角if (top > pondModelHeight - sonNodeHeight) {top = pondModelHeight - sonNodeHeight;}if (left > pondModelWidth - sonNodeWidth) {left = pondModelWidth - sonNodeWidth;}item.dx = left;item.dy = top;item.zIndex = 999;};document.onmouseup = (e) => {console.log("放开事件");document.onmousemove = null;document.onmouseup = null;item.zIndex = 1;odiv = null;};
};
</script>

css：本来不该放出来，但是我在这里踩坑了，觉得其他人也会（img图片有默认的拖拽，很难禁止，所以拿一个伪元素直接放在img上面，不给点img就不会踩坑）

      .range {width: 960px;height: 540px;background-color: pink;position: relative;.iconItem {position: absolute;left: 10px;top: 10px;z-index: 2;display: flex;align-items: center;cursor: move;user-select: none;width: 32px;height: 32px;background: yellow;img {width: 32px;height: 32px;}// 关键&::before {content: " ";width: 100%;height: 100%;position: absolute;top: 0;left: 0;z-index: 3;}&:hover {// span {//   display: block;// }}span {display: none;font-size: 12px;font-family: YouSheBiaoTiHei;color: red;}}}

完整代码：（建议按照上面的一点点复制吧，有几个文件是外部的base64图片）

<template><div class="PastureMap"><div class="mapContent"><div class="mapBox"><div class="range" id="range" ref="range"><divclass="iconItem"v-for="(item, index) in pointList":key="index"@mousedown.stop.prevent.native="mousedown($event, item)":style="{left: item.dx + 'px',top: item.dy + 'px','z-index': item.zIndex,}"><![e-mail]="mousemove($event, item)"@mouseup.stop.prevent.native="mouseup($event, item)"--><imgdraggable="false":src="typeList[item.type].src":alt="typeList[item.type].name + item.EName"/><span>{{ typeList[item.type].name + item.EName }}</span></div></div></div><div class="operationPanel"><div class="addIConCard"><div class="title"><span>新增图标</span></div><div class="box"><div class="bgImg"><div class="left"><span>背景图：</span></div><div class="right"><button>选择图片</button><span>建议尺寸：960*540</span></div></div><div class="iconBtnForm"><div class="cell"><div class="left"><span>圈舍</span></div><div class="right"><input type="text" placeholder="请选择圈舍" /></div></div><div class="cell"><div class="left"><span>设备编号</span></div><div class="right"><input type="text" placeholder="请输入设备编号" /></div></div><div class="cell"><div class="left"><span>类型</span></div><div class="right"><input type="text" placeholder="请选择类型" /></div></div></div><div class="addBtn"><button>新增</button></div></div></div><div class="iconList"><div class="item" v-for="(item, index) in pointList" :key="index"><div class="left"><span>类型</span></div><div class="right"><input type="text" placeholder="名称" /></div><div class="del"><img src="" alt="del" /></div></div></div></div></div></div>
</template><script setup lang="ts">
import { ref, reactive, watch, computed, Ref } from "vue";
import { mapPunctuation } from "@/utils/youran";
let rem = ref(0.005208); // 10/1920const range: Ref = ref(null);
let typeList = reactive([{type: 1,src: "",name: "球机-摄像头",},{type: 2,src: "",name: "抢机-摄像头",},{type: 3,src: "",name: "无源打卡设备",},{type: 4,src: "",name: "无源打卡设备",},{type: 5,src: "",name: "反向控制",},
]);typeList.forEach((item, index) => {item.src = mapPunctuation[index].src;
});let pointList = ref([{fId: "111",type: 1,EId: "",EName: "",dx: 0,dy: 0,zIndex: 2,},
]);// 鼠标事件
let downType = ref(false);
let disX = 0;
let disY = 0;
let odiv: any = null;
let mousedown = (e: any, item: any) => {downType.value = true;console.log("按下事件");odiv = e.target;disX = e.clientX - odiv.offsetLeft;disY = e.clientY - odiv.offsetTop;document.onmousemove = (e) => {console.log("移动事件");//计算元素位置(需要判断临界值)let left = e.clientX - disX;let top = e.clientY - disY;let { offsetHeight: pondModelHeight, offsetWidth: pondModelWidth } =range.value;let { offsetHeight: sonNodeHeight, offsetWidth: sonNodeWidth } = odiv;// 左上角(left)if (left < 0) {left = 0;}if (top < 0) {top = 0;}// 左下角if (top > pondModelHeight - sonNodeHeight) {top = pondModelHeight - sonNodeHeight;}if (left > pondModelWidth - sonNodeWidth) {left = pondModelWidth - sonNodeWidth;}item.dx = left;item.dy = top;item.zIndex = 999;};document.onmouseup = (e) => {console.log("放开事件");document.onmousemove = null;document.onmouseup = null;item.zIndex = 1;odiv = null;};
};
</script><style lang="less" scoped>
.PastureMap {height: 100%;.mapContent {display: flex;height: 100%;.mapBox {flex: 1;height: 100%;.range {width: 960px;height: 540px;background-color: pink;position: relative;.iconItem {position: absolute;left: 10px;top: 10px;z-index: 2;display: flex;align-items: center;cursor: move;user-select: none;width: 32px;height: 32px;background: yellow;img {width: 32px;height: 32px;}&::before {content: " ";width: 100%;height: 100%;position: absolute;top: 0;left: 0;z-index: 3;}&:hover {// span {//   display: block;// }}span {display: none;font-size: 12px;font-family: YouSheBiaoTiHei;color: red;}}}}.operationPanel {width: 270px;.addIConCard {.title {span {}}.box {.bgImg {display: flex;align-items: center;.left {}.right {}}.iconBtnForm {.cell {display: flex;align-items: center;.left {span {}}.right {input {}}}}}}.iconList {.item {display: flex;align-items: center;position: relative;.left {span {}}.right {input {}}.del {position: absolute;top: 0;right: 0;}}}}}
}
</style>