A doubt releated with Ajax auto fill controll

hi all

I want to fill all employees name in my employee table according to the text typed in textbox

i uses auto fill extender

<asp:TextBox ID="TextBox1" runat="server" AutoPostBack="True"></asp:TextBox>
<cc1:AutoCompleteExtender runat="server" ID="autoComplete1" TargetControlID="TextBox1"
ServiceMethod="GetEmpDetails1" ServicePath="~/PayRoll/webservice/hr1service.asmx" MinimumPrefixLength="1"
CompletionSetCount="10">
</cc1:AutoCompleteExtender>

and in web service the method

[WebMethod]

public string GetEmpDetails1(string as_EmpName, int count)
{


using (AdminBusinussFacade.FacadeCommon fum = new AdminBusinussFacade.FacadeCommon())
{
DataSet ds_empsearch = fum.ff_fillddlRelation("", as_EmpName,"","Webser_search", "", "");

DataTable dt = ds_empsearch.Tables[0];

string s = "";


for (int i = 0; i < dt.Rows.Count; i++)
{
s = s + dt.Rows[i][0].ToString() + "/" + dt.Rows[i][1].ToString() +" "+ dt.Rows[i][2].ToString()+" "+dt.Rows[i][3].ToString()+" "+"["+dt.Rows[i][4].ToString()+"]" + " Branch" + "/";

}
return s;
}
}
But it doesnt works
Plz give a solution for this

Thanks in Advance

Regards

Amrutha