model弹出框居中

Modal.prototype.adjustDialog = function () {
var modalIsOverflowing = this.$element[0].scrollHeight > document.documentElement.clientHeight

this.$element.css({
paddingLeft:  !this.bodyIsOverflowing && modalIsOverflowing ? this.scrollbarWidth : ‘‘,
paddingRight: this.bodyIsOverflowing && !modalIsOverflowing ? this.scrollbarWidth : ‘‘
})
// 弹出框居中
var $modal_dialog = $(this.$element[0]).find(‘.modal-dialog‘);
var m_top = ( $(window).height() - $modal_dialog.height() )/2;
$modal_dialog.css({‘margin‘: m_top + ‘px auto‘});
}