grid view and create user wizard control

i have grid view in which there is a text box and i want that the data of this text box i actomaticaly copy to the create user wizard control username text box plz help me in this
i have try this code but it have some error
Grid View cod
<asp:GridView runat="server" ID="grid" AutoGenerateColumns="true" >
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:TextBox ID="lbUserName" Text='<%# Eval("UserName") %>' runat="server" ></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>

custom creat user wizard code
<asp:CreateUserWizard ID="CreateUserWizard1" runat="server">
<WizardSteps>
<asp:CreateUserWizardStep ID="CreateUserWizardStep1" runat="server">
<ContentTemplate>

<table style="font-size: 10pt; font-family: Verdana" border="0" width="400"> ...