问如果日期在Gridview中不同，则在行之间插入空格

EN

DataRow lastRow = null;
protected void GrdidView_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        DataRow thisRow = ((DataRowView) e.Row.DataItem).Row;
        if(lastRow != null) // only add separators between two rows
        {
            DateTime thisDate = thisRow.Field<DateTime>("ColumnName");
            DateTime lastDate = lastRow.Field<DateTime>("ColumnName");
            if (thisDate.Date != lastDate.Date)
            {
                e.Row.Style.Add("border-top-width", "20px");
            }
        }
        lastRow = thisRow;
    }
}

<asp:GridView runat="server" id="GridView" AutoGenerateColumns="False" >
    <Columns>
            <asp:TemplateField>
               <ItemTemplate>
                <asp:Literal runat="server" id="ltDate" Text='<%#Bind("MyDate")%>' />
                </ItemTemplate>
            </asp:TemplateField>
    </Columns>
</asp:GridView>

private void GridView_PreRender(object sender, System.EventArgs e)
    {
    string sCompareDate = "";
    foreach (GridViewRow gvRow in GridView.Rows) {
        //First Row
        if (string.IsNullOrEmpty(sCompareDate))
            sCompareDate = ((Literal)gvRow.FindControl("ltDate")).Text;

        if (sCompareDate != ((Literal)gvRow.FindControl("ltDate")).Text) {
            gvRow.Cells(0).Attributes.Add("style", "border-bottom-width:30px;");
            sCompareDate = ((Literal)gvRow.FindControl("ltDate")).Text;
    }
}
}