//渐渐的消失 for (int iNum = 10; iNum >= 0; iNum --) { //变更窗体的不透明度 this.Opacity = 0.1 * iNum; //暂停 System.Threading.Thread.Sleep(100); } //渐渐的显示 for (int iNum = 0; iNum <= 10; iNum ++) { //变更窗体的不透明度 this.Opacity = 0.1 * iNum; //暂停 System.Threading.Thread.Sleep(100); }