TOOLTIP add in dropdownlist for makink item text clear

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C#

ASP.NET

I have some dropdown which i am filling on page load . on page load method i call a function and pass this dropdown to this function and bind it and same time i am adding tooltip to this dropdown ,it is working fine .

Note:- This Function called in page load and


if(!IsPostBack)
{
BindlistControlls.FillListBox(CurrentUser, ddlReAllocation, "ALLOC TYPE", CurrentSystem, "", "", "", CurrentCompany, false,"","","");
}


ddlReAllocation is the name of dropdownlist but when i perform select index change then tooltip does not add in this drop down so can you tell me what should i do?