新增加拖动指令

src/directive/index.js

@@ -1,9 +1,11 @@
 import hasRole from './permission/hasRole'
 import hasPermi from './permission/hasPermi'
 import clipboard from './module/clipboard'
+import drag from './module/drag'
 
 export default function directive(app){
   app.directive('hasRole', hasRole)
   app.directive('hasPermi', hasPermi)
 	app.directive('clipboard', clipboard)
+	app.directive('drag', drag)
 }

src/directive/module/drag.js

@@ -0,0 +1,121 @@
+/**
+ * 自定义拖动指令
+ * @description  使用方式：v-drag="[dragDom,dragHeader]"，如 `<div v-drag="['.el-dialog', '.el-dialog__header']"></div>`
+ * @description dragDom 要拖动的元素，dragHeader 要拖动的 Header 位置
+ * @link 注意：https://github.com/element-plus/element-plus/issues/522
+ * @lick 参考：https://blog.csdn.net/weixin_46391323/article/details/105228020?utm_medium=distribute.pc_relevant.none-task-blog-baidujs_title-10&spm=1001.2101.3001.4242
+ */
+export default {
+  mounted(el, binding) {
+    if (!binding.value) return false;
+
+    const dragDom = document.querySelector(binding.value[0]);
+    const dragHeader = document.querySelector(binding.value[1]);
+
+    dragHeader.onmouseover = () => (dragHeader.style.cursor = `move`);
+
+    function down(e, type) {
+      // 鼠标按下，计算当前元素距离可视区的距离
+      const disX = type === 'pc' ? e.clientX - dragHeader.offsetLeft : e.touches[0].clientX - dragHeader.offsetLeft;
+      const disY = type === 'pc' ? e.clientY - dragHeader.offsetTop : e.touches[0].clientY - dragHeader.offsetTop;
+
+      // body当前宽度
+      const screenWidth = document.body.clientWidth;
+      // 可见区域高度(应为body高度，可某些环境下无法获取)
+      const screenHeight = document.documentElement.clientHeight;
+
+      // 对话框宽度
+      const dragDomWidth = dragDom.offsetWidth;
+      // 对话框高度
+      const dragDomheight = dragDom.offsetHeight;
+
+      const minDragDomLeft = dragDom.offsetLeft;
+      const maxDragDomLeft = screenWidth - dragDom.offsetLeft - dragDomWidth;
+
+      const minDragDomTop = dragDom.offsetTop;
+      const maxDragDomTop = screenHeight - dragDom.offsetTop - dragDomheight;
+
+      // 获取到的值带px 正则匹配替换
+      let styL = getComputedStyle(dragDom).left;
+      let styT = getComputedStyle(dragDom).top;
+
+      // 注意在ie中 第一次获取到的值为组件自带50% 移动之后赋值为px
+      if (styL.includes('%')) {
+        styL = +document.body.clientWidth * (+styL.replace(/\%/g, '') / 100);
+        styT = +document.body.clientHeight * (+styT.replace(/\%/g, '') / 100);
+      } else {
+        styL = +styL.replace(/\px/g, '');
+        styT = +styT.replace(/\px/g, '');
+      }
+
+      return {
+        disX,
+        disY,
+        minDragDomLeft,
+        maxDragDomLeft,
+        minDragDomTop,
+        maxDragDomTop,
+        styL,
+        styT,
+      };
+    }
+
+    function move(e, type, obj) {
+      let { disX, disY, minDragDomLeft, maxDragDomLeft, minDragDomTop, maxDragDomTop, styL, styT } = obj;
+
+      // 通过事件委托，计算移动的距离
+      let left = type === 'pc' ? e.clientX - disX : e.touches[0].clientX - disX;
+      let top = type === 'pc' ? e.clientY - disY : e.touches[0].clientY - disY;
+
+      // 边界处理
+      if (-left > minDragDomLeft) {
+        left = -minDragDomLeft;
+      } else if (left > maxDragDomLeft) {
+        left = maxDragDomLeft;
+      }
+
+      if (-top > minDragDomTop) {
+        top = -minDragDomTop;
+      } else if (top > maxDragDomTop) {
+        top = maxDragDomTop;
+      }
+
+      // 移动当前元素
+      dragDom.style.cssText += `;left:${left + styL}px;top:${top + styT}px;`;
+    }
+
+    /**
+     * pc端
+     * onmousedown 鼠标按下触发事件
+     * onmousemove 鼠标按下时持续触发事件
+     * onmouseup 鼠标抬起触发事件
+     */
+    dragHeader.onmousedown = (e) => {
+      const obj = down(e, 'pc');
+      document.onmousemove = (e) => {
+        move(e, 'pc', obj);
+      };
+      document.onmouseup = () => {
+        document.onmousemove = null;
+        document.onmouseup = null;
+      };
+    };
+
+    /**
+     * 移动端
+     * ontouchstart 当按下手指时，触发ontouchstart
+     * ontouchmove 当移动手指时，触发ontouchmove
+     * ontouchend 当移走手指时，触发ontouchend
+     */
+    dragHeader.ontouchstart = (e) => {
+      const obj = down(e, 'app');
+      document.ontouchmove = (e) => {
+        move(e, 'app', obj);
+      };
+      document.ontouchend = () => {
+        document.ontouchmove = null;
+        document.ontouchend = null;
+      };
+    };
+  }
+}