Populate Two TextFields based on DropDownList selection

hi, in my form Drop Down List available 50 items. i have found bellow code so as per bellow code i have to make 50 cases. updating 50 cases will take lot of time. is there any other code available that i can easily copy paste all the details??. i mean first i will copy all drop down options & then corresponding auto population options. thanks..

     var sNewSel = event.value;
     switch (sNewSel) {
       case "ProductNo1":
         this.getField("ItemDescription").value = "blah, blah";
         this.getField("Size").value = "blah, blah";
         break;

     case "ProductNo2":
         this.getField("ItemDescription").value = "blah, blah";
         this.getField("Size").value = "blah, blah";
         break;

     case "ProductNo3":
        this.getField("ItemDescription").value = "blah, blah";
        this.getField("Size").value = "blah, blah";
         break;

     //etc.
     }