禁止图片拖拽
method1
img{pointer-events:none} ，firefox支持，IE不支持
method2
<body ondragstart='return false'></body> || img{ondragstart='return false'}
method3
<body onselectstart='return false' onselectstart='no' style="-moz-user-select:none;">
method4
obj.onmousemove=function(ev){
ev.preventDefault()
}
method5
obj.onmouseenter=function(ev){
//设置捕获
this.setCapture && this.setCapture()
}
obj.onmouseleave=function(ev){
//清除捕获
this.releaseCapture && this.releaseCapture()
}
禁止文字选中
body{
-webkit-touch-callout: none;
-webkit-user-select: none;
-khtml-user-select: none;
-moz-user-select: none;
-ms-user-select: none;
user-select: none;
}