Multiple Valuefields in DropDown Selection

Hi,
 
In DropDown i want to pass the multiple Value fields . How to pass
 
Ex:
  Job Code (PK) Item Code (PK) Item 1 1 A 1 2 B 1 3 c 2 1 D 2 2 c
 
ddl.TextField="Item"
ddl.Valuefield="...."
 
Please help me to solve this issue... ...