get the layer in server

[yanli]

how to i get a layer from server

var lays:ArrayCollection=new ArrayCollection();      
    lays=myDynamicService.layerInfos;
    var layy:Layer=new Layer();
         
    layy=lays.getItemAt(0);//i know this is error

how do  i get a layer from server,then put the layer  to ???layy??? as a  Parameter

[yanli]

i  just get  two layer of server  as the Parameters of GP . i do it as the above.
can you help Modify error