How to check check box in dynatree by id

Question

i am having dynatree, whose node.data.key is in form of 'TD_1','TD_3','TD_7'.

I am storing this id's into db.

Then i am having dropdown, whose change event will give me that id i.e TD_3.

Using which i have to select the node.

$(container).dynatree({
                checkbox: true,
                selectMode: 3,
                generateIds: true,
                autoCollapse: false,
                children: data
            });