基于Vue实现拖拽效果

参考地址：基于Vue实现拖拽效果

参考链接中讲的比较详细，我只使用了其中自定义指令的方法。整体代码如下：

<template>
    <!-- 卡片 -->
    <div class="card" v-drag id="card">

    </div>
</template>

<script>
export default {
    data() {
        return {
        }
    },
    directives: {
        drag: {
            // 指令的定义
            bind: function(el) {
                let oDiv = el;  // 获取当前元素
                oDiv.onmousedown = (e) => {
                    // 算出鼠标相对元素的位置
                    let disX = e.clientX - oDiv.offsetLeft;
                    let disY = e.clientY - oDiv.offsetTop;

                    document.onmousemove = (e) => {
                        // 用鼠标的位置减去鼠标相对元素的位置，得到元素的位置
                        let left = e.clientX - disX;
                        let top = e.clientY - disY;

                        oDiv.style.left = left + 'px';
                        oDiv.style.top = top + 'px';
                    };

                    document.onmouseup = (e) => {
                        document.onmousemove = null;
                        document.onmouseup = null;
                    }
                }
            }
        }
    }
}
</script>

<style lang="scss">
    .card {
        position: absolute;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%);
        width: 870px;
        height: 510px;
        background-color: #3ab5a0;
    }
</style>

使用方法：在需拖拽功能的元素上添加v-drag启用：

补充：阻止拖拽

上述方法利用自定义指令实现了弹窗的拖拽，补充部分是阻止拖拽，例如：弹窗中有input框，如果想要选中input中的内容就需要阻止弹窗的拖拽

参考地址：vue实现弹窗拖拽

export default {
    directives: {
        /*自定义拖拽*/
        drag: {
            inserted: function(el, binding, vnode) {
                var odiv = el.parentNode;
                odiv.onmousedown = function(eve) {
                    eve = eve || window.event;
                    var clientX = eve.clientX;
                    var clientY = eve.clientY;
                    var odivX = odiv.offsetLeft;
                    var odivY = odiv.offsetTop;
                    var odivLeft = clientX - odivX;
                    var odivTop = clientY - odivY;
                    var clientWidth = document.documentElement.clientWidth;
                    var oWidth = odiv.clientWidth;
                    var odivRight = clientWidth - oWidth;
                    var clientHeight = document.documentElement.clientHeight;
                    var oHeight = odiv.clientHeight;
                    var odivBottom = clientHeight - oHeight;
                    document.onmousemove = function(e) {
                        e.preventDefault();
                        var left = e.clientX - odivLeft;
                        if (left < 0) {
                            left = 0
                        }
                        if (left > odivRight) {
                            left = odivRight
                        }
                        var Top = e.clientY - odivTop;
                        if (Top < 0) {
                            Top = 0
                        }
                        if (Top > odivBottom) {
                            Top = odivBottom
                        }
                        odiv.style.left = left + "px";
                        odiv.style.top = Top + "px";
                    }
                    document.onmouseup = function() {
                        document.onmouseup = "";
                        document.onmousemove = "";
                    }
                }
            }
        },
        /*阻止拖拽*/
        stopdrag: {
            inserted: function(el, binding, vnode) {
                let element = el;
                element.onmousedown = function(e) {
                    e.stopPropagation()
                }
            }
        }
    }
}

　使用方法：在不需拖拽的元素上添加v-stopdrag阻止：