placeholder技能在IE中损坏的解决方式转载

* {
    margin:0;
    padding:0;
    border:0;
}
*,*:after,*:before {
    -webkit-box-sizing:border-box;
    -moz-box-sizing:border-box;
    box-sizing:border-box;
}
input {
    display:block;
    margin:20px auto;
    width:500px;
    height:50px;
    border:2px solid #ccc;
    padding:0 20px;
}

;(function($) {
    $.fn.placeholder = function(options) {
        var opts = $.extend({}, $.fn.placeholder.defaults, options);
        var isIE = document.all ? true : false;
        return this.each(function() {
            var _this = this,
                placeholderValue = _this.getAttribute("placeholder"); //缓存默认的placeholder值
            if (isIE) {
                _this.setAttribute("value", placeholderValue);
                _this.onfocus = function() {
                    $.trim(_this.value) == placeholderValue ? _this.value = "" : ;
                };
                _this.onblur = function() {
                    $.trim(_this.value) == "" ? _this.value = placeholderValue : ;
                };
            }
        });
    };
})(jQuery);

$("input").placeholder();