In php if you call json_encode it will add slashes to your sting, but if you want to use update_optionn just want url without slashes. Here is a easy to let you remove slahes in json
Last day one of my client told me his site was hacked. Then I help him removed all malware codes from his site. But today he said the site was hacked again. His hosting provided his some log and pointed out it may cauded by the plugin of RevolutionSlider . Because his site is too old and the plugin is integrated into the theme so he cannot upgrade RevolutionSlider directly, to avoid beening hacked again, I did some small changes to privent the vulnerability.