在GridView中获得动态TextBox和Text的值

<asp:GridView ID="GridView1" runat="server" HeaderStyle-VerticalAlign="Middle" AutoGenerateColumns="false" CssClass="gridview" HeaderStyle-HorizontalAlign="Center">
<Columns>
<asp:TemplateField HeaderText="******" ItemStyle-HorizontalAlign="Center" HeaderStyle-Width="50" ItemStyle-CssClass="rowid">
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "dwFishType")%>
</ItemTemplate>
</asp:TemplateField>

<asp:TemplateField HeaderText="******" HeaderStyle-Width="100">
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "dwBulletScore").ToString()%>
</ItemTemplate>
</asp:TemplateField>

<asp:TemplateField HeaderText="******" HeaderStyle-Width="100">
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "dwGameScore").ToString()%>
</ItemTemplate>
</asp:TemplateField>

<asp:TemplateField HeaderText="******" HeaderStyle-Width="100">
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "dwFactLines").ToString()%>
</ItemTemplate>
</asp:TemplateField>

<asp:TemplateField HeaderText="******" HeaderStyle-Width="100">
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "dwCurLines").ToString()%>
</ItemTemplate>
</asp:TemplateField>

<asp:TemplateField HeaderText="******" HeaderStyle-Width="100">
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "dwAccuracy").ToString()%>
</ItemTemplate>
</asp:TemplateField>

<asp:TemplateField HeaderText="******" HeaderStyle-Width="100">
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "dwFishScore").ToString()%>
</ItemTemplate>
</asp:TemplateField>

<asp:TemplateField HeaderText="******" HeaderStyle-Width="100">
<ItemTemplate>
<asp:Panel ID="Panel1" DefaultButton="Button1" runat="server">
<asp:TextBox ID="txtBox" runat="server" Text='<%# DataBinder.Eval(Container.DataItem, "dwAccuracy").ToString() %>' Width="50" Height="25" BorderStyle="none" />
<asp:Button ID="Button1" Text="确认修改" runat="server" Width="50" Height="25" Enabled="true" OnClick="btnChange" ToolTip='<%# DataBinder.Eval(Container.DataItem, "dwFishType").ToString() %>' />
</asp:Panel>
</ItemTemplate>

</asp:TemplateField>
</Columns>
</asp:GridView>

protected void btnChange(object sender, EventArgs e)
{
Button bt = (Button)sender;
string TextValue = "";
Panel pan = (Panel)bt.Parent;
TextBox txt = (TextBox)pan.FindControl("txtBox");
TextValue = txt.Text.ToString();
Response.Write("<script>alert('" + TextValue + "'); history.go(-1);</script>");
}