protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e) 
{
}

<asp:GridView ID="GridView1" runat="server" HeaderStyle-BorderWidth="1px" BorderWidth="1px"
    EnableModelValidation="True" AutoGenerateColumns="False" OnRowEditing="GridView1_RowEditing"
    OnRowCancelingEdit="GridView1_RowCancelingEdit" OnRowUpdating="GridView1_RowUpdating"
    OnRowUpdated="GridView1_RowUpdated" CellPadding="3" BackColor="White" BorderColor="#CCCCCC"
    BorderStyle="Solid" Width="35%" EnableViewState="true" OnRowDataBound="GridView1_RowDataBound">
    <Columns>
        <asp:CommandField ShowEditButton="True" />
        <asp:BoundField DataField="KpiName_Acc" SortExpression="KpiName_Acc" HeaderText="Перечень KPI"
            ItemStyle-Width="60px" ItemStyle-Wrap="True" ItemStyle-HorizontalAlign="Left"
            InsertVisible="False" ReadOnly="True" ControlStyle-Width="10px" HeaderStyle-Wrap="true">
            <ControlStyle Width="10px"></ControlStyle>
            <HeaderStyle Wrap="True"></HeaderStyle>
            <ItemStyle HorizontalAlign="Left" Wrap="True" Width="60px"></ItemStyle>
        </asp:BoundField>
        <asp:TemplateField HeaderText="Вес"  SortExpression="WeightValue">
            <EditItemTemplate>
                <asp:TextBox ID="Textbox1" runat="server" Text='<%# Bind("WeightValue") %>'></asp:TextBox>
            </EditItemTemplate>
            <ItemTemplate>
                <asp:Label ID="Label1" runat="server" Text='<%# String.Format("{0:0%}",Eval("WeightValue")) %>'></asp:Label>
            </ItemTemplate>
        </asp:TemplateField>
            <asp:BoundField DataField="Target" SortExpression="Target" HeaderText="Цель" HeaderStyle-Width="60px" HeaderStyle-Wrap="true"
            DataFormatString="{0:F}" ItemStyle-HorizontalAlign="Center">
            <HeaderStyle Wrap="True" Width="60px"></HeaderStyle>
            <ItemStyle HorizontalAlign="Center"></ItemStyle>
        </asp:BoundField>
       </Columns>
    
</asp:GridView>