Legend for time series plots

[ankit agrawal]

Hi,

Can someone please suggest what will be the right/easiest way to include a legend for multiple time series plots in a single graph. 

I further want that legend be interactive and dynamic. 

By interactive, I meant something like a toggle button in legend for each plot. And by dynamic I mean legends shows up and disappear based on what all plots are being shown. 

Thank You!