JSFiddle - React, Tailwind, and code Playground

JavaScript

SID="18608202881669&Act=432&Mode=1&CLk=T&Key58=6003&dotnetdll=TopCoConfigurator.dll&dotnetfunc=CasingSizeSummary&SID=18608202881669&F=&J=CasingSize/CasingSizeSummary.asp&Key58=6003&ccs_casingsizeid=6003";

var re = /&J=(.*?)&Key/;
SID = SID.replace(re, '');
alert(SID);