There are certain characters I cannot pass in an HTML page parameter because it causes errors. Some are obvious "&,+" some are less obvious "#".

I want users to input a form. And then I made a custom HTML page to display their results. But if the form values contain characters I cannot pass through as a parameter, the page will not display properly.

I DO NOT want the HTML page to fetch the form data.

Is there a function I can call that will catch entries that cannot pass as a parameter? getalphanumeric removes spaces and periods which I need to keep.

Interestingly the spaces are automatically converted into the html friendly "percent 20" but the other characters are not.

Is there a list of all the characters which need to be removed or changed and I can manually code to have those characters removed/changed or warn the user not to use those characters in submissions?