Initializes a new Font using a specified size and unit. Sets the style to FontStyle.Regular.
The FontFamily of the new Font.
The em-size of the new font in the units specified by the unit parameter.
The GraphicsUnit of the new font.
family is null.
emSize is less than or equal to 0, evaluates to infinity, or is not a valid number.
The resulting font has its Style property set to FontStyle.Regular.