How to overwrite a inbuilt control method in C#

I am working with c# Windows application and in one of requrements I need to chage the parameters of a method of the inbuilt c#.net control. can any one please help me regarding this.

See the Line 1 开发者_StackOverflowbelow the custom tooltip have method called "show" here it will take only controls as the references to show the Tooltip I need to change the method some thing like Line-2

1. CustomTooltip.Show("", control1);
2. CustomTooltip.Show("", SomeText);

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You might want to know about WinForm user control. Please visit this MSDN page for more details.

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You could derive from the control that you want to extend:

public class MyTextBox: TextBox
{
    ... override the methods you need
}