Dropdown value set in javascript

Question

Hi every one 

 

 

i am find code two textbox select date in two textbox date difference value bind dropdown list

i am achive find date difference but dropdown selected value not set

in javascript please help anyone ..

 

this code used already:- 

 

1. > document.getElementById("<%=ddldays.ClientID %>").value = days; 

 

2 .> var element = document.getElementById("ddldays");

element.value = days;