//placeholder兼容方法（兼容IE8以上浏览器）            var JPlaceHolder = {                //检测                _check: function () {                    return 'placeholder' in document.createElement('input');                },                //初始化                init: function () {                    if (!this._check()) {                        this.fix();                    }                },                //修复                fix: function () {                    jQuery(':input[placeholder]').each(function (index, element) {                        var self = $(this), txt = self.attr('placeholder');                        self.wrap($('
     
').css({                            position: 'relative',                            zoom: '1',                            border: 'none',                            background: 'none',                            padding: 'none',                            margin: 'none'                        }));                        var pos = self.position(), h = self.outerHeight(true), paddingleft = self.css('padding-left');                         //此处的css样式，根据情况修改                        var holder = $('').text(txt).css({                            position: 'absolute',                            left: pos.left,                            // top: pos.top,                            height: h + 'px',                            lineHeight: h + 'px',                            paddingLeft: paddingleft,                            color: '#aaa',                            paddingTop: '15px',                            textAlign: 'center',                            width: '347px'                        }).appendTo(self.parent());                        self.focusin(function (e) {                            holder.hide();                        }).focusout(function (e) {                            if (!self.val()) {                                holder.show();                            }                        });                        holder.click(function (e) {                            holder.hide();                            self.focus();                        });                    });                }            };            //执行placeholder兼容方法            jQuery(function () {                JPlaceHolder.init();            });