Here is one way using the POSIX strtol function: 
    #!/usr/bin/perl -wl

    use strict;
    use POSIX 'strtol';

    sub is_hex {
        local $!;
        return ! (POSIX::strtol($_[0], 16))[1];
    }


    my @hex = (0x1234, 1234, "0X1234", "beetroot", "decade", "fax");

    print is_hex($_), "\t", $_ for @hex;


    __END__
    Prints:

    1       4660
    1       1234
    1       0X1234
            beetroot
    1       decade
            fax

[download]

--
John.

In reply to Re: Validating Hex Numbers by jmcnamara
in thread Validating Hex Numbers by HiFoo

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