PHP and JS determine whether a string is a number

PHP and JS determine whether a string is a number

1. PHP: is_numeric() function, if it is a number or a numeric string, it returns true, otherwise it returns false

2. JS: isNaN() function, if If it is a number, it will return false, if it is not, it will return true

').addClass('pre-numbering').hide(); $(this).addClass('has-numbering').parent().append($numbering); for (i = 1; i ').text(i)); }; $numbering.fadeIn(1700); }); });

The above introduces PHP and JS to determine whether a string is a number, including aspects of it. I hope it will be helpful to friends who are interested in PHP tutorials.