JavaScript function to built redirect URL

We need to build a JavaScript function that will read the below elements from the form / array and built a redirect URL. These elements relate to selections made by a user using the form to filter for vendors providing a service they need (like say Plumbers, Carpenters and so on). 1. Vendor IDs (multiple vendor ids separated by an under-score) 2. Category 3. Location Once these are read and available we need to construct a Redirect URL in the below format: [login to view URL] Please see the attached screen for the array object that currently exists which will provide the vendor id. To reiterate, only the vendors selected by a user need to be read and added to the Redirect URL. This URL needs to be available so that we can attach to a button which when clicked will redirect the user to the lead-collection page. Code needs to be adequately commented. Please note the milestones as below: Upto 20% as down payment for starting the project 30% on successful demonstration of full functionality through screen share Final 50% on code delivery and deployment (allow 1-2 days for testing) Thanks for your interest.