.NET事件 - 什么是对象发件人& EventArgs e？ [英] .NET Events - What are object sender & EventArgs e?

问题描述

发件人和eventArgs是什么意思/引用？如何使用它们（对于下面的情况）？

What do sender and eventArgs mean/refer to? How can I make use of them (for the scenario below)?

场景：

我正在尝试使用delete函数构建一个自定义控件，并且我想要删除在包含许多相同的自定义控件的页面上点击的控件。

I'm trying to build a custom control with a delete function, and I want to be able to delete the control that was clicked on a page that contains many of the same custom control.

推荐答案

发件人是操作的控件（例如OnClick，它是按钮）。

The sender is the control that the action is for (say OnClick, it's the button).

EventArgs是此事件的实施者可能会发现有用。使用OnClick它没有什么好的，但在某些事件中，就像在GridViewSelectedIndexChanged中说的那样，它将包含新的索引或其他有用的数据。

The EventArgs are arguments that the implementor of this event may find useful. With OnClick it contains nothing good, but in some events, like say in a GridView 'SelectedIndexChanged', it will contain the new index, or some other useful data.

什么克里斯说可以这样做：

What Chris is saying is you can do this:

protected void someButton_Click (object sender, EventArgs ea)
{
    Button someButton = sender as Button;
    if(someButton != null)
    {
        someButton.Text = "I was clicked!";
    }
}

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