button style from cs code

Hi,
How to add style to a buttton from the cs code.
I created a button, and rather than adding text, i want to attach an image to it from cs code. I have an image in the Images folder.
private Button btnNewButton; btnNewButton = new Button(); btnNewButton.Click += new EventHandler(btnNewButton_Click); this.Controls.Add(btnNewButton);
From the design, I can do this:
<input id="Button2" type="button" style="background-image: url(images/Welcome.jpg); " />
How to style the button from the cs code.
Thank you
 
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