When I add the fieldset to the page
<ext:FieldSet id="FieldSet1" runat="server" Height="400px" Width="200px"  Title="123">
in the page ,I set this fieldset title to new value
FieldSet1.SetTitle(e.Parameters("set1").Trim.ToStr ing) //if value of set1 is 'Customer'

when I get this fieldset's title ,also it is "123",why it is not 'Customer',and how can I get this title is 'Customer'
Ext.Msg.Alert(FieldSet1.Title, FieldSet1.Title).Show()