面试题整理-创新互联

.box2{ width: 200px; height: 200px; background-color: red; padding: 50px; border:10px solid green; margin: 20px; box-sizing:border-box;}

box-sizing:border-box;加了这个之后width包含padding和border  所以实际宽度是减去这两个的值

IE7及以下浏览器不兼容

box-sizing:border-box;弹出的宽度是200px

.box2{ width: 200px; height: 200px; background-color: red; padding: 50px; border:10px solid green; margin: 20px; }

实际弹出的宽度是200px  不包含padding的

2&3//22|3//3NaN==NaN //falseundefined == undefined //truenull == null //truetypeof(undefined) //"undefined"typeof(null) //"object"typeof([])//"object"