1. Class 实体是引用类型,但传入方法时是null的情况在子方法中不论怎么赋值当 FirstService.SetPerson(person,ref tempMsg); 执行后Person都是null:如图1和图2: 但当在 Index2 方法中为person 实例化后就可以如-Person person = new Person ();,当调用FirstService.SetPerson(person,ref tempMsg);方法后person的值会随SetPerson方法中赋值而改变
1.TreeView选择事件执行两次 Very often, we need to execute some code in SelectedItemChanged depending on the selected TreeViewItem. ButSelectedItemChanged is called twice. This is due to stealing focus from the main window, which is screwing something up. Wha
Mouseenter在鼠标滑上去不会对其子元素也发生监听, Mouseover在鼠标滑上去会对其子元素发生监听. 所以对于事件的监听,我们要看需求,这里是对父元素的监听,不需要对子元素做监听.就用mouseenter与mouseleave. mouseenter是不会对其里面的子元素做监听,所以我们对这个li做mouseenter和mouseleave的监听就是正确的. 带settimeout的mouseover事件 function add_color(b){ var x='#'+b; var