序：工作中突然接到新需求，管理系统需要嵌入地图，作为前端，我负责出页面，老大说，地图上面的搜索框要可拖拽
但是搜索框是有点击事件的，点击显隐下拉菜单，如果拖拽的事件源选择select框的话，会有样式（十字拖动符cursor:move与selelt默认点击的箭头）冲突
思索良久，就用外边距区域做事件源啊，废话不多，看代码。。。。
1、html页面放置的select搜索框（注意看哦，重点是h6标签哦）

2、以下是样式
#searchbox {
border:1px solid #fff;
position:absolute;
left:50px;
top:50px;
}
#searchbox select{
width:350px;
height: 40px;
}
#searchbox h6.search-top {
position:absolute;
top:-6px;
left:0;
width:100%;
height:6px;
line-height:6px;
color:white;
cursor:move;
}
#searchbox h6.search-bottom {
position:absolute;
bottom:-6px;
left:0;
width:100%;
height:6px;
line-height:6px;
color:white;
cursor:move;
}
#searchbox h6.search-left {
position:absolute;
bottom:0;
left:-6px;
width:6px;
height:100%;
color:white;
cursor:move;
}
#searchbox h6.search-right {
position:absolute;
bottom:0;
right:-6px;
width:6px;
height:100%;
color:white;
cursor:move;
}
3、以下是js方法哦（方法有参考某个童鞋的，时间久忘记名字了，此处不明示了，理解一下哦）
function drag(obj) {
if (typeof obj === 'string') {
var obj = document.getElementById(obj);
} else {
var obj = obj;
}
function fixEvent(event) {
event.target = event.srcElement;
event.preventDefault = fixEvent.preventDefault;
return event;
}
fixEvent.preventDefault = function () {
this.returnValue = false;
};
obj.onmousedown = mousedown;
function mousedown(e) {
var e = e || fixEvent(window.event);
var disX = e.clientX - obj.offsetLeft;
var disY = e.clientY - obj.offsetTop;
if (e.target.tagName === 'H6') {
document.onmousemove = move;
document.onmouseup = up;
} else {
document.onmousemove = null;
document.onmouseup = null;
}
function move(e) {
var e = e || fixEvent(window.event);
var left = e.clientX - disX;
var top = e.clientY - disY;
if (obj.setCapture) {
obj.setCapture();
}
if (left < 0) {
left = 0;
} else if (left > document.documentElement.clientWidth - obj.offsetWidth) {
left = document.documentElement.clientWidth - obj.offsetWidth;
}
if (top < 0) {
top = 0;
} else if (top > document.documentElement.clientHeight - obj.offsetHeight) {
top = document.documentElement.clientHeight - obj.offsetHeight;
}
obj.style.left = left + 'px';
obj.style.top = top + 'px';
return false;
};
function up() {
if (obj.releaseCapture) {
obj.releaseCapture();
}
document.onmousemove = null;
document.onmouseup = null;
}
};
}
4、然后是js页面调用方法
window.onload = function () {
var trigger = document.getElementById('searchbox');
drag(trigger);
};
综上：此拖拽事件已搞定，如有问题留言探讨，转载请注明出处。