Hi dorsa,

Refer below sample.

Refer below link to crud operation using sqldatasource.

Insert Update Edit Delete record in GridView using SqlDataSource in ASP.Net

HTML

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataKeyNames="CustomerId"
    OnRowUpdating="OnRowUpdating" DataSourceID="SqlDataSource1">
    <Columns>
        <asp:TemplateField HeaderText="Name" SortExpression="Title">
            <EditItemTemplate>
                <asp:DropDownList ID="DropDownList1" runat="server">
                    <asp:ListItem>Mudassar</asp:ListItem>
                    <asp:ListItem>John</asp:ListItem>
                    <asp:ListItem>Robert</asp:ListItem>
                </asp:DropDownList>
            </EditItemTemplate>
            <ItemTemplate>
                <asp:Label ID="Label1" runat="server" Text='<%# Bind("Name") %>'></asp:Label>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:BoundField DataField="CustomerId" HeaderText="CustomerId" ReadOnly="True" SortExpression="CustomerId"
            InsertVisible="False" />
        <asp:TemplateField HeaderText="Country" SortExpression="Country">
            <EditItemTemplate>
                <asp:TextBox runat="server" ID="txtCountry" Text='<%#Eval("Country") %>' />
            </EditItemTemplate>
            <ItemTemplate>
                <asp:Label ID="lblCountry" runat="server" Text='<%# Bind("Country") %>'></asp:Label>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:CommandField ButtonType="Link" ShowEditButton="true" ShowDeleteButton="true"
            ItemStyle-Width="150" />
    </Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:TestConnectionString %>"
    SelectCommand="SELECT * FROM [Customers]" UpdateCommand="UPDATE [Customers] SET [Name] = @Name, [Country] = @Country WHERE [CustomerId] = @CustomerId"
    OnUpdating="sqlDtSrcEditCourse_Updating">
    <UpdateParameters>
        <asp:Parameter Name="CustomerId" Type="Int32" />
        <asp:Parameter Name="Name" Type="String" />
        <asp:Parameter Name="Country" Type="String" />
    </UpdateParameters>
</asp:SqlDataSource>

Code

C#

int customerId;
string name;
string country;
protected void OnRowUpdating(object sender, GridViewUpdateEventArgs e)
{
    GridViewRow row = GridView1.Rows[e.RowIndex];
    customerId = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Values[0]);
    country = (row.FindControl("txtCountry") as TextBox).Text;
    name = (row.FindControl("DropDownList1") as DropDownList).SelectedValue;
    SqlDataSource1.Update();
}

protected void sqlDtSrcEditCourse_Updating(object sender, SqlDataSourceCommandEventArgs e)
{
    try
    {
        e.Command.Parameters["@Name"].Value = name;
        e.Command.Parameters["@Country"].Value = country;
        e.Command.Parameters["@CustomerId"].Value = customerId;
    }
    catch
    {

    }
}

VB.Net

Private customerId As Integer
Private name As String
Private country As String

Protected Sub OnRowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
    Dim row As GridViewRow = GridView1.Rows(e.RowIndex)
    customerId = Convert.ToInt32(GridView1.DataKeys(e.RowIndex).Values(0))
    country = (TryCast(row.FindControl("txtCountry"), TextBox)).Text
    name = (TryCast(row.FindControl("DropDownList1"), DropDownList)).SelectedValue
    SqlDataSource1.Update()
End Sub

Protected Sub sqlDtSrcEditCourse_Updating(ByVal sender As Object, ByVal e As SqlDataSourceCommandEventArgs)
    Try
        e.Command.Parameters("@Name").Value = name
        e.Command.Parameters("@Country").Value = country
        e.Command.Parameters("@CustomerId").Value = customerId
    Catch
    End Try
End Sub

Screenshot