Question

Is it possible to manage task's constraints with the GTP .Net 3.0 Component (ie: task1 begin after task 2, task 1 end when task 2 begin, task 1 start 3 month after task 4 etc... like with MS project) ?

And so, is-it possible to draw links starting from the start date of a task and joining the end date of another (with the demo I was only able to join task with end date from the first one and start date of the sconde one) ?

Answer

Task constraints are normaly part of your business logic and not a primaliry concearn for a GUI control, but we offer several events like OnTimeItem_AfterMove that you will want to implement to enforce your rules.

You can also use the TimeItemLinkActions that are available on each link. The LinkAction can be set to some simple rules on how to behave when a TimeItem changes: TimeItemLinkActions are executed when the time items in the link are changed (Start or Stop is changed). LinkActions can help you enforce some of the business rules that you want to stay in effect when the user changes time items

To control where the link is rooted you set the TimeItemLinkStyle property of the link to one of the values :

StartToStart Start of one time item to another time items start. 
StartToStop Start of one time item to another time items stop. 
StopToStart Stop of one time item to another time items start. 
StopToStop Stop of one time item to another time items start.