Display Multiple DropDownList in ASP.Net GridView EditItemTemplate on Edit Mode

Hey dorsa,

Please refer below sample.

HTML

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" BackColor="White"
    BorderColor="#CCCCCC" BorderStyle="None" BorderWidth="1px" CellPadding="3" Width="869px"
    Font-Names="Tahoma" AutoGenerateEditButton="True" Style="margin-left: 0px" OnRowEditing="GridView1_RowEditing">
    <Columns>
        <asp:BoundField DataField="Code" HeaderText="کد واحد" SortExpression="Code" />
        <asp:TemplateField HeaderText="WeekDay" SortExpression="WeekDay" ItemStyle-Width="150px">
            <EditItemTemplate>
                <asp:DropDownList ID="DropDownList1" runat="server">
                    <asp:ListItem>شنبه</asp:ListItem>
                    <asp:ListItem>یکشنبه</asp:ListItem>
                    <asp:ListItem>دوشنبه</asp:ListItem>
                    <asp:ListItem>سه شنبه</asp:ListItem>
                    <asp:ListItem>چهارشنبه</asp:ListItem>
                    <asp:ListItem>پنج شنبه</asp:ListItem>
                    <asp:ListItem>جمعه</asp:ListItem>
                </asp:DropDownList>
            </EditItemTemplate>
            <ItemTemplate>
                <asp:Label ID="Label1" runat="server" Text='<%# Bind("WeekDay") %>'></asp:Label>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="ساعت شروع" SortExpression="StartTime" ItemStyle-Width="250px">
            <EditItemTemplate>
                <asp:DropDownList ID="ListStartHour3" runat="server" CssClass="TextBox-Align" TabIndex="8"
                    ValidationGroup="Validate1">
                    <asp:ListItem></asp:ListItem>
                    <asp:ListItem>08</asp:ListItem>
                    <asp:ListItem>09</asp:ListItem>
                    <asp:ListItem>10</asp:ListItem>
                    <asp:ListItem>11</asp:ListItem>
                    <asp:ListItem>12</asp:ListItem>
                    <asp:ListItem>13</asp:ListItem>
                    <asp:ListItem>14</asp:ListItem>
                    <asp:ListItem>15</asp:ListItem>
                    <asp:ListItem>16</asp:ListItem>
                    <asp:ListItem>17</asp:ListItem>
                    <asp:ListItem>18</asp:ListItem>
                    <asp:ListItem>19</asp:ListItem>
                    <asp:ListItem>20</asp:ListItem>
                </asp:DropDownList>
                <asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" ControlToValidate="ListStartHour3"
                    ErrorMessage="*"></asp:RequiredFieldValidator>
                &nbsp;:
                <asp:DropDownList ID="ListStartMinute3" runat="server" CssClass="TextBox-Align" TabIndex="8"
                    ValidationGroup="Validate1">
                    <asp:ListItem></asp:ListItem>
                    <asp:ListItem>00</asp:ListItem>
                    <asp:ListItem>15</asp:ListItem>
                    <asp:ListItem>30</asp:ListItem>
                    <asp:ListItem>45</asp:ListItem>
                </asp:DropDownList>
                <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="ListStartMinute3"
                    ErrorMessage="*"></asp:RequiredFieldValidator>
            </EditItemTemplate>
            <ItemTemplate>
                <asp:Label ID="Label2" runat="server" Text='<%# Bind("StartTime") %>'></asp:Label>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText=" EndTime" SortExpression="EndTime" ItemStyle-Width="250">
            <EditItemTemplate>
                <asp:DropDownList ID="ListEndHour1" runat="server" CssClass="TextBox-Align" TabIndex="9"
                    ValidationGroup="Validate1">
                    <asp:ListItem></asp:ListItem>
                    <asp:ListItem>08</asp:ListItem>
                    <asp:ListItem>09</asp:ListItem>
                    <asp:ListItem>10</asp:ListItem>
                    <asp:ListItem>11</asp:ListItem>
                    <asp:ListItem>12</asp:ListItem>
                    <asp:ListItem>13</asp:ListItem>
                    <asp:ListItem>14</asp:ListItem>
                    <asp:ListItem>15</asp:ListItem>
                    <asp:ListItem>16</asp:ListItem>
                    <asp:ListItem>17</asp:ListItem>
                    <asp:ListItem>18</asp:ListItem>
                    <asp:ListItem>19</asp:ListItem>
                    <asp:ListItem>20</asp:ListItem>
                </asp:DropDownList>
                <asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server" ControlToValidate="ListEndHour1"
                    ErrorMessage="*"></asp:RequiredFieldValidator>
                &nbsp;:
                <asp:DropDownList ID="ListEndMinute1" runat="server" CssClass="TextBox-Align" TabIndex="9"
                    ValidationGroup="Validate1">
                    <asp:ListItem></asp:ListItem>
                    <asp:ListItem>00</asp:ListItem>
                    <asp:ListItem>15</asp:ListItem>
                    <asp:ListItem>30</asp:ListItem>
                    <asp:ListItem>45</asp:ListItem>
                </asp:DropDownList>
                <asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" ControlToValidate="ListEndMinute1"
                    ErrorMessage="*"></asp:RequiredFieldValidator>
            </EditItemTemplate>
            <ItemTemplate>
                <asp:Label ID="Label3" runat="server" Text='<%# Bind("EndTime") %>'></asp:Label>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:BoundField DataField="Title" HeaderText="Title" SortExpression="Title" />
        <asp:BoundField DataField="Description" HeaderText="توضیحات" SortExpression="Description" />
    </Columns>
    <EmptyDataTemplate>
        <span style="font-family: tahoma">there isn't any defined session for this course</span>
    </EmptyDataTemplate>
    <FooterStyle BackColor="White" ForeColor="#000066" />
    <HeaderStyle BackColor="#006699" Font-Bold="True" ForeColor="White" />
    <PagerStyle BackColor="White" ForeColor="#000066" HorizontalAlign="Left" />
    <RowStyle ForeColor="#000066" />
    <SelectedRowStyle BackColor="#669999" Font-Bold="True" ForeColor="White" />
    <SortedAscendingCellStyle BackColor="#F1F1F1" />
    <SortedAscendingHeaderStyle BackColor="#007DBB" />
    <SortedDescendingCellStyle BackColor="#CAC9C9" />
    <SortedDescendingHeaderStyle BackColor="#00547E" />
</asp:GridView>

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        BindGrid();
    }
}

private void BindGrid()
{
    System.Data.DataTable dt = new System.Data.DataTable();
    dt.Columns.AddRange(new System.Data.DataColumn[] { new System.Data.DataColumn("Code", typeof(int)), 
        new System.Data.DataColumn("WeekDay", typeof(string)),
        new System.Data.DataColumn("StartTime", typeof(int)), 
        new System.Data.DataColumn("EndTime", typeof(int)), 
        new System.Data.DataColumn("Title", typeof(string)), 
        new System.Data.DataColumn("Description", typeof(string)) });
    dt.Rows.Add(1, "Monday", 10, 12, "t1", "rjhfiuhg");
    dt.Rows.Add(2, "TuesDay", 12, 14, "t1", "rjhfiuhg");
    dt.Rows.Add(3, "Friday", 15, 18, "t1", "rjhfiuhg");
    GridView1.DataSource = dt;
    GridView1.DataBind();
}
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
    GridView1.EditIndex = e.NewEditIndex;
    this.BindGrid();
}

Screenshot