I am having a prob in collection object...My prob is Server sends a data and i have to save the data in flexgrid.I am using this data as a key and for the reference i am saving flexgrid row number with key. If another data comes.i just want to refer the collection and if exists in collection , using the row number i want to replace in flexgrid. If its not exists then add in a new row of flexgrid... I am new to programming. so i dont know how to get the key and how to store row number with the key.. getting lot of confusion.. pls help me to solve this..