Indicates whether the specified Unicode character is categorized as a decimal digit.
Parameters
c
The Unicode character to evaluate.
Returns
true if c is a decimal digit; otherwise, false.
Remarks
This method determines whether a type_tis a radix-10 digit. This contrasts with is_number, which determines whether a Char is of any numeric Unicode category. Numbers include characters such as fractions, subscripts, superscripts, Roman numerals, currency numerators, encircled numbers, and script-specific digits.