Event Handling in .NET framework

Hi All,
As I am new to .NET framework.
I have a doubt in Event handling.
For example to handle a button click we write a delegate as
private void button1_Click(object sender, EventArgs e)
In this function I can change the sender object value means I can do what ever I want to do with Button object.
Why this is implemented in this way in Framework.
Is this good to do so.
Please help me to understand this. Thanks in advance.
Regards,

Arvind







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