xdigit_value

Determines the numeric value of a character as a hexadecimal digit.

If the character is not a hex digit according to [func@GLib.ascii_isxdigit], `-1` is returned.

Differs from [func@GLib.unichar_xdigit_value] because it takes a char, so there's no worry about sign extension if characters are signed.

Differs from [func@GLib.unichar_xdigit_value] because it takes a char, so there's no worry about sign extension if characters are signed.

Example: Convert a char-digit to hex-digit:

public static int main (string[] args) {
	// Output:
	//  ``'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ``
	//  ``'A', 'B', 'C', 'D', 'E', 'F', 'a', 'b', 'c', 'd', ``
	//  ``'e', 'f', ``
	for (int i = 0; i <= 255; i++) {
		if (((char) i).xdigit_value () >= 0) {
			print ("'%c', ", (char) i);
		}
	}
	print ("\n");
	return 0;
}

valac --pkg glib-2.0 char.xdigit_value.vala

Parameters:

c	an ASCII character

Returns:

the numerical value of c if it is a hex digit, `-1` otherwise