String of value pairs to object array, encoded.

stringtoKvpEnc1.js

//Extract key-values from string in the format of 'k1=v1&k2=v2&k3=v3' (with uri decoding)
String.prototype.ToKvps = function(){
var qd={};
this.split`&`.forEach(item => {let [k,v] = item.split`=`; v = v && decodeURIComponent(v);
                      (qd[k] = qd[k] || []).push(v)}); 
                      return qd;
}

//Example: JSON.stringify("fd=44&ds=32&dks=1314%41&sd=39%209&ds=dsl%20ds".ToKvps());
//Output:  "{"fd":["44"],"ds":["32","dsl ds"],"dks":["1314A"],"sd":["39 9"]}"