解决jquery slideUp 方法闪动的问题

var n = t - this.startTime;var dur = this.options.duration;this.state = n / dur;// Perform the easing function, defaults to swingvar specialEasing = this.options.specialEasing && this.options.specialEasing[this.prop];var defaultEasing = this.options.easing || (jQuery.easing.swing ? "swing" : "linear");this.pos = jQuery.easing[specialEasing || defaultEasing](this.state, n, 0, 1, this.options.duration);this.now = this.start + ((this.end - this.start) * this.pos);// Perform the next step of the animation//if is contractif(this.end == 0){if(this.now < 1){this.step(true);}else{this.update();}}else{//else is expendthis.update();}