vue Element,el-dialog彈出層拖拽及拉伸、雙擊全屏

以下復制用就行，使用vue-element-admin后台模版的的彈窗拖拽的，直接復制到el-drag-dialog文件下的drag.js替換原來的就可以了

import Vue from 'vue';

/*

*  使用方法

*  將以下代碼復制到一個js文件中，然后在入口文件main.js中import引入即可；

*  給elementUI的dialog上加上 v-dialogDrag 指令就可以實現彈窗的全屏和拉伸了。

*  給dialog設置 :close-on-click-modal="false" , 禁止點擊遮罩層關閉彈出層

*  如果是form表單，不要將提交等按鈕放置el-form-item，以免在上下拉伸時被隱藏

*/

// v-dialogDrag: 彈窗拖拽+水平方向伸縮

Vue.directive('dialogDrag', {

    bind(el, binding, vnode, oldVnode) {

        //彈框可拉伸最小寬高

        let minWidth = 400;

        let minHeight = 300;

        //初始非全屏

        let isFullScreen = false;

        //當前寬高

        let nowWidth = 0;

        let nowHight = 0;

        //當前頂部高度

        let nowMarginTop = 0;

        //獲取彈框頭部（這部分可雙擊全屏）

        const dialogHeaderEl = el.querySelector('.el-dialog__header');

        //彈窗

        const dragDom = el.querySelector('.el-dialog');

        //給彈窗加上overflow auto；不然縮小時框內的標簽可能超出dialog；

        dragDom.style.overflow = "auto";

        //清除選擇頭部文字效果

        //dialogHeaderEl.onselectstart = new Function("return false");

        //頭部加上可拖動cursor

        dialogHeaderEl.style.cursor = 'move';

        // 獲取原有屬性 ie dom元素.currentStyle 火狐谷歌 window.getComputedStyle(dom元素, null);

        const sty = dragDom.currentStyle || window.getComputedStyle(dragDom, null);

        let moveDown = (e) => {

            // 鼠標按下，計算當前元素距離可視區的距離

            const disX = e.clientX - dialogHeaderEl.offsetLeft;

            const disY = e.clientY - dialogHeaderEl.offsetTop;

            // 獲取到的值帶px 正則匹配替換

            let styL, styT;

            // 注意在ie中 第一次獲取到的值為組件自帶50% 移動之后賦值為px

            if (sty.left.includes('%')) {

                styL = +document.body.clientWidth * (+sty.left.replace(/\%/g, '') / 100);

                styT = +document.body.clientHeight * (+sty.top.replace(/\%/g, '') / 100);

            } else {

                styL = +sty.left.replace(/\px/g, '');

                styT = +sty.top.replace(/\px/g, '');

            };

            document.onmousemove = function (e) {

                // 通過事件委托，計算移動的距離

                const l = e.clientX - disX;

                const t = e.clientY - disY;

                // 移動當前元素 

                dragDom.style.left = `${l + styL}px`;

                dragDom.style.top = `${t + styT}px`;

                //將此時的位置傳出去

                //binding.value({x:e.pageX,y:e.pageY})

            };

            document.onmouseup = function (e) {

                document.onmousemove = null;

                document.onmouseup = null;

            };

        }

        dialogHeaderEl.onmousedown = moveDown;

        //雙擊頭部全屏效果

        dialogHeaderEl.ondblclick = (e) => {

            if (isFullScreen == false) {

                nowHight = dragDom.clientHeight;

                nowWidth = dragDom.clientWidth;

                nowMarginTop = dragDom.style.marginTop;

                dragDom.style.left = 0;

                dragDom.style.top = 0;

                dragDom.style.height = "100VH";

                dragDom.style.width = "100VW";

                dragDom.style.marginTop = 0;

                isFullScreen = true;

                dialogHeaderEl.style.cursor = 'initial';

                dialogHeaderEl.onmousedown = null;

            } else {

                dragDom.style.height = "auto";

                dragDom.style.width = nowWidth + 'px';

                dragDom.style.marginTop = nowMarginTop;

                isFullScreen = false;

                dialogHeaderEl.style.cursor = 'move';

                dialogHeaderEl.onmousedown = moveDown;

            }

        }

        dragDom.onmousemove = function (e) {

            let moveE = e;

            if (e.clientX > dragDom.offsetLeft + dragDom.clientWidth - 10 || dragDom.offsetLeft + 10 > e.clientX) {

                dragDom.style.cursor = 'w-resize';

            } else if (el.scrollTop + e.clientY > dragDom.offsetTop + dragDom.clientHeight - 10) {

                dragDom.style.cursor = 's-resize';

            } else {

                dragDom.style.cursor = 'default';

                dragDom.onmousedown = null;

            }

            dragDom.onmousedown = (e) => {

                const clientX = e.clientX;

                const clientY = e.clientY;

                let elW = dragDom.clientWidth;

                let elH = dragDom.clientHeight;

                let EloffsetLeft = dragDom.offsetLeft;

                let EloffsetTop = dragDom.offsetTop;

                dragDom.style.userSelect = 'none';

                let ELscrollTop = el.scrollTop;

                //判斷點擊的位置是不是為頭部

                if (clientX > EloffsetLeft && clientX < EloffsetLeft + elW && clientY > EloffsetTop && clientY < EloffsetTop + 100) {

                    //如果是頭部在此就不做任何動作，以上有綁定dialogHeaderEl.onmousedown = moveDown;

                }else{

                    document.onmousemove = function (e) {

                        e.preventDefault(); // 移動時禁用默認事件

                        //左側鼠標拖拽位置

                        if (clientX > EloffsetLeft && clientX < EloffsetLeft + 10) {

                            //往左拖拽

                            if (clientX > e.clientX) {

                                dragDom.style.width = elW + (clientX - e.clientX) * 2 + 'px';

                            }

                            //往右拖拽

                            if (clientX < e.clientX) {

                                if(dragDom.clientWidth < minWidth){

                                }else{

                                    dragDom.style.width = elW - (e.clientX - clientX) * 2 + 'px';

                                }

                            }

                        }

                        //右側鼠標拖拽位置

                        if (clientX > EloffsetLeft + elW - 10 && clientX < EloffsetLeft + elW) {

                            //往左拖拽

                            if (clientX > e.clientX) {

                                if (dragDom.clientWidth < minWidth) {

                                } else {

                                    dragDom.style.width = elW - (clientX - e.clientX) * 2 + 'px';

                                }

                            }

                            //往右拖拽

                            if (clientX < e.clientX) {

                                dragDom.style.width = elW + (e.clientX - clientX) * 2 + 'px';

                            }

                        }

                        //底部鼠標拖拽位置

                        if (ELscrollTop + clientY > EloffsetTop + elH - 20 && ELscrollTop + clientY < EloffsetTop + elH) {

                            //往上拖拽

                            if (clientY > e.clientY) {

                                if (dragDom.clientHeight < minHeight) {

                                } else {

                                    dragDom.style.height = elH - (clientY - e.clientY) * 2 + 'px';

                                }

                            }

                            //往下拖拽

                            if (clientY < e.clientY) {

                                dragDom.style.height = elH + (e.clientY - clientY) * 2 + 'px';

                            }

                        }

                    };

                    //拉伸結束

                    document.onmouseup = function (e) {

                        document.onmousemove = null;

                        document.onmouseup = null;

                    };

                }

            }

        }

    }

})

代碼來源於：Element,el-dialog彈出層拖拽及拉伸、雙擊全屏