C++ iswxdigit()

The iswxdigit() function is defined in <cwctype> header file.

iswxdigit() prototype

int iswxdigit(wint_t ch);

The iswxdigit() function checks if ch is a hexadecimal numeric character as classified by the current C locale. The available hexadecimal numeric characters are:

• Digits (0 to 9)
• Lowercase alphabets from a to f
• Uppercase alphabets from A to F

iswxdigit() Parameters

• ch: The wide character to check.

iswxdigit() Return value

• The iswxdigit() function returns non zero value if ch is a hexadecimal numeric character.
• It returns zero if ch is not a hexadecimal numeric character.

Example: How iswxdigit() function works?

#include <cwctype>
#include <iostream>
#include <cwchar>
#include <clocale>
using namespace std;

void ishexadecimal(wchar_t *str)
{
	bool flag = false;
	for (int i=0; i<wcslen(str); i++)
	{
		if (!iswxdigit(str[i]))
		{
			flag = true;
			break;
		}
	}

	if (flag)
		wcout << str << L" is not a valid hexadecimal number" << endl;
	else
		wcout << str << L" is a valid hexadecimal number" << endl;
}

int main()
{
	setlocale(LC_ALL, "en_US.UTF-8");

	wchar_t str[] = L"ă3ë1f";
	ishexadecimal(str);

	wchar_t str1[] = L"12abf";
	ishexadecimal(str1);

	return 0;
}

When you run the program, the output will be:

ă3ë1f is not a valid hexadecimal number
12abf is a valid hexadecimal number