Dynamically create buttons, how to specify only the location, do not specify the size?

When dynamically create a button to set frame
button.frame = CGRectMake (100,100,100,100);
The above code sets the position and size, but I do not want to set the size of the button you want to use the default size should be how to write ah.
Reply:
Nobody Dinga
Reply:
. Center =

Reply:
[Button setOrigin: CGPointMake (100,100)];
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