我想从这个函数范围内取消的事件。
I want to cancel an event from within that function scope.
例如。我pressed按钮单击事件和错误的验证,我想取消本次活动。同样,我想取消其他事件也。
Eg. I pressed button click event and on false validation, I want to cancel this event. Likewise i want to cancel other events also.
我怎样才能做到这一点在C#
How can i do this in C#
这取决于具体的方案;在大多数情况下:不是的取消的情况下,只是什么也不做,例如:
It depends on the scenario; in most cases: rather than cancel the event, just do nothing, for example:
private void SaveDataClicked(object sender, EventArgs args) {
if(!ValidateData()) return;
// [snip: code that does stuff]
}
或
private void SaveDataClicked(object sender, EventArgs args) {
if(ValidateData()) {
// [snip: code that does stuff]
}
}
有一些事件,暴露出 CancelEventArgs
(或类似),允许取消一些的外部的行为通过的args
- 形式闭合是最明显的例子(设置 e.Cancel = TRUE;
)。
There are some events that expose a CancelEventArgs
(or similar), allowing to to cancel some external behaviour via the args
- form-closing being the most obvious example (set e.Cancel = true;
).
请注意,在这种情况下我也不会按钮自动对话框的结果;是时手动(如果)将处理程序成功完成。
Note that in this scenario I would not have an automatic dialog-result on the button; apply that manually when (if) the handler completes successfully.