How to properly send a packet on a button click.

[c-ab-o-o-s-e]

All I am wanting to do is properly send a packet to the server and handle it properly when a user clicks a button in the Inventory. I have not messed with these before and looking at source code I have the packets setup and ready to go. I just don't know how to pass the button Id properly. Like wont I need the cordinates for where the TileEntity is? So in the gui when I send the packet I will need to send the TileEntity with it? I seen some people do the

modID.network.sendToServer()

and the

modID.network.getPacketFrom()

I don't know which one to use. My issue is that I got to see it finished to understand it. If I had a good source code that shows a process like that I would look at that. I tired looking at Mekanism, but seems like its all over the place. I'm pretty sure once I figure this one out afterwards it wont be too hard to understand. I got the Message class and all the needed classes for to send the packet I just don't know how to link it.

[c-ab-o-o-s-e]

ok so I would send the packet

ModID.network.sendToServer(new MessageGuiButton(button.id));

and then in the Handler class have the onMessage() take in the Id and get the player, container, and finally the TileEntity. And since we are getting the TileEntity that way it already knows what one we are talking about. Is that correct?