控件 control (n.); controls; rich edit control rich edit; up-down control up-down; visual basic activex control visual basic activex; widget; wmi control
Typically , request events signal a visual change for one or more components ; for example , clicking on a graphic in a tree control may expand a branch of the tree 最典型的有请求事件可能会触发了一个或多个组件的显示变化;例如当点击一个树型控件可能会展开它的分支。
Alternatively , an event in one component may update the visual representation of another component ; for example , clicking on a leaf node in a tree may cause an associated list to change its contents and redisplay 另外,某个组件的事件可能会更新另一个组件的显示;例如当点击一个树型控件的叶节点可能会导致和它关联的列表控件改变它的内容和显示。