PHP url encryption and decryption function

base64_encode syntax: string base64_decode(string data);
*/
$str='d3d3ljexmwnulm5ldnk7vtu9zlpmzfg='; //Define string
echo base64_decode($str); //www.111cn.net Yiju Tutorial Network                         Output the decoded content/*
base64_encode syntax: string base64_encode(string data);
*/
$str='www.111cn.net Yiju Tutorial Network'; //Define string
echo base64_encode($str); // d3d3ljexmwnulm5ldnk7vtu9zlpmzfg=             // Output the encoded content
$returnUrl = rawurlencode(base64_encode($returnUrl));   // Encoding    
$returnUrl = parse_str(base64_decode($returnUrl)); // Decode or
$returnUrl = base64_decode( $returnUrl);//Decoding
//or
//I don’t know why, the first decoding method above returns null, solve
$returnUrl = base64_encode($returnUrl); //Encoding
$returnUrl = base64_decode($ returnUrl);//Decoding
This is a way, but it is the safest, because as long as you know this principle, you can unlock it, but your requirements are not high so this is fine.