The variable VEH that is defined implicitly in the event handler is seen by all activities inside the event handler and scopes nested inside the event handler.

在事件程序中隐式定义的变量 VEH 对事件处理程序和事件处理程序内嵌套的范围内的所有活动可见。

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A local variable is one that is only available for use (that is, you can assign to it, or fetch its value) within the scope in which it is declared, and within nested scopes as well.

本地变量是仅可以在声明它的范围中和嵌套范围中使用的变量(也就是说，您可以向其赋值，也可以从中取值)。

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The variable VM defined in MainScope is seen by all activities within MainScope and by all activities inside the event handler associated with MainScope and scopes nested inside the event handler

在 MainScope 内定义的变量 VM 对 MainScope 内的所有活动和与 MainScope 关联的事件处理程序及事件处理程序内的嵌套范围内的所有活动可见

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