(C#) ASP.NET AccessDataSource & GridView ItemCommand

<%@ Page Language="C#" Debug="true" %>
<script runat="server">
		AccessDataSource myDSource;
		string strSQL;
		void Page_Load(object sender, EventArgs e)
		{
		    
		    myDSource = new AccessDataSource();
		    myDSource.DataFile = "~/database/mydatabase.mdb";
		    
		    if (!Page.IsPostBack) {
		        BindData();
		    }
		}

		void BindData()
		{
		    
		    myDSource.SelectCommand = "SELECT * FROM [customer]";

		    //*** BindData to GridView ***'
		    myGridView.DataSource = myDSource;
		    myGridView.DataBind();
		    
		    myDSource = null;
		    
		}

		void modEditCommand(object sender, GridViewEditEventArgs e)
		{
		    myGridView.EditIndex = e.NewEditIndex;
		    myGridView.ShowFooter = false;
		    BindData();
		}

		void modCancelCommand(object sender, GridViewCancelEditEventArgs e)
		{
		    myGridView.EditIndex = -1;
		    myGridView.ShowFooter = true;
		    BindData();
		}

		void modDeleteCommand(object sender, GridViewDeleteEventArgs e)
		{
		    strSQL = "DELETE FROM customer WHERE CustomerID = '" + myGridView.DataKeys[e.RowIndex].Value + "'";
		    
	        myDSource.DeleteCommand = strSQL;
	        myDSource.DeleteCommandType = SqlDataSourceCommandType.Text;
	        myDSource.Delete();
		    
		    myGridView.EditIndex = -1;
		    BindData();
		}


		void myGridView_RowCommand(object source, GridViewCommandEventArgs e)
		{
		    if (e.CommandName == "Add") {
		        //*** CustomerID ***'
		        TextBox txtCustomerID = (TextBox)myGridView.FooterRow.FindControl("txtAddCustomerID");
		        //*** Email ***'
		        TextBox txtName = (TextBox)myGridView.FooterRow.FindControl("txtAddName");
		        //*** Name ***'
		        TextBox txtEmail = (TextBox)myGridView.FooterRow.FindControl("txtAddEmail");
		        //*** CountryCode ***'
		        TextBox txtCountryCode = (TextBox)myGridView.FooterRow.FindControl("txtAddCountryCode");
		        //*** Budget ***'
		        TextBox txtBudget = (TextBox)myGridView.FooterRow.FindControl("txtAddBudget");
		        //*** Used ***'
		        TextBox txtUsed = (TextBox)myGridView.FooterRow.FindControl("txtAddUsed");
		        
		        strSQL = "INSERT INTO customer (CustomerID,Name,Email,CountryCode,Budget,Used) " + 
				" VALUES ('" + txtCustomerID.Text + "','" + txtName.Text + "','" + txtEmail.Text + "' " + 
				" ,'" + txtCountryCode.Text + "','" + txtBudget.Text + "','" + txtUsed.Text + "') ";
		        
	            myDSource.InsertCommand = strSQL;
	            myDSource.InsertCommandType = SqlDataSourceCommandType.Text;
	            myDSource.Insert();
		        
		        BindData();
		    }
		}


		void modUpdateCommand(object s, GridViewUpdateEventArgs e)
		{
		    
		    //*** CustomerID ***'
		    TextBox txtCustomerID = (TextBox)myGridView.Rows[e.RowIndex].FindControl("txtEditCustomerID");
		    //*** Email ***'
		    TextBox txtName = (TextBox)myGridView.Rows[e.RowIndex].FindControl("txtEditName");
		    //*** Name ***'
		    TextBox txtEmail = (TextBox)myGridView.Rows[e.RowIndex].FindControl("txtEditEmail");
		    //*** CountryCode ***'
		    TextBox txtCountryCode = (TextBox)myGridView.Rows[e.RowIndex].FindControl("txtEditCountryCode");
		    //*** Budget ***'
		    TextBox txtBudget = (TextBox)myGridView.Rows[e.RowIndex].FindControl("txtEditBudget");
		    //*** Used ***'
		    TextBox txtUsed = (TextBox)myGridView.Rows[e.RowIndex].FindControl("txtEditUsed");
		    
		    strSQL = "UPDATE customer SET CustomerID = '" + txtCustomerID.Text + "' " + 
			" ,Name = '" + txtName.Text + "' " + " ,Email = '" + txtEmail.Text + "' " + 
			" ,CountryCode = '" + txtCountryCode.Text + "' " + " ,Budget = '" + txtBudget.Text + "' " +
			" ,Used = '" + txtUsed.Text + "' " + " WHERE CustomerID = '" + myGridView.DataKeys[e.RowIndex].Value + "'";
		    
	        myDSource.UpdateCommand = strSQL;
	        myDSource.UpdateCommandType = SqlDataSourceCommandType.Text;
	        myDSource.Update();
		    
		    myGridView.EditIndex = -1;
		    myGridView.ShowFooter = true;
		    BindData();
		}


</script>
<html>
<head>
    <title>ThaiCreate.Com ASP.NET - AccessDataSource</title>
</head>
<body>
<form id="form1" runat="server">
<asp:GridView id="myGridView" runat="server" AutoGenerateColumns="False" 
	ShowFooter="True" 
	DataKeyNames="CustomerID"
	OnRowEditing="modEditCommand"
	OnRowCancelingEdit="modCancelCommand"
	OnRowDeleting="modDeleteCommand"
	OnRowUpdating="modUpdateCommand"
	OnRowCommand="myGridView_RowCommand">

	<Columns>

	<asp:TemplateField HeaderText="CustomerID">
		<ItemTemplate>
			<asp:Label id="lblCustomerID" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.CustomerID") %>'></asp:Label>
		</ItemTemplate>
		<EditItemTemplate>
			<asp:TextBox id="txtEditCustomerID" size="5" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.CustomerID") %>'></asp:TextBox>
		</EditItemTemplate>
		<FooterTemplate>
			<asp:TextBox id="txtAddCustomerID" size="5" runat="server"></asp:TextBox>
		</FooterTemplate>
	</asp:TemplateField>

	<asp:TemplateField HeaderText="Name">
		<ItemTemplate>
			<asp:Label id="lblName" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Name") %>'></asp:Label>
		</ItemTemplate>
		<EditItemTemplate>
			<asp:TextBox id="txtEditName" size="10" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Name") %>'></asp:TextBox>
		</EditItemTemplate>
		<FooterTemplate>
			<asp:TextBox id="txtAddName" size="10" runat="server"></asp:TextBox>
		</FooterTemplate>
	</asp:TemplateField>

	<asp:TemplateField HeaderText="Email">
		<ItemTemplate>
			<asp:Label id="lblEmail" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Email") %>'></asp:Label>
		</ItemTemplate>
		<EditItemTemplate>
			<asp:TextBox id="txtEditEmail" size="20" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Email") %>'></asp:TextBox>
		</EditItemTemplate>
		<FooterTemplate>
			<asp:TextBox id="txtAddEmail" size="20" runat="server"></asp:TextBox>
		</FooterTemplate>
	</asp:TemplateField>

	<asp:TemplateField HeaderText="CountryCode">
		<ItemTemplate>
			<asp:Label id="lblCountryCode" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.CountryCode") %>'></asp:Label>
		</ItemTemplate>
		<EditItemTemplate>
			<asp:TextBox id="txtEditCountryCode" size="2" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.CountryCode") %>'></asp:TextBox>
		</EditItemTemplate>
		<FooterTemplate>
			<asp:TextBox id="txtAddCountryCode" size="2" runat="server"></asp:TextBox>
		</FooterTemplate>
	</asp:TemplateField>

	<asp:TemplateField HeaderText="Budget">
		<ItemTemplate>
			<asp:Label id="lblBudget" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Budget") %>'></asp:Label>
		</ItemTemplate>
		<EditItemTemplate>
			<asp:TextBox id="txtEditBudget" size="6" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Budget") %>'></asp:TextBox>
		</EditItemTemplate>
		<FooterTemplate>
			<asp:TextBox id="txtAddBudget" size="6" runat="server"></asp:TextBox>
		</FooterTemplate>
	</asp:TemplateField>

	<asp:TemplateField HeaderText="Used">
		<ItemTemplate>
			<asp:Label id="lblUsed" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Used") %>'></asp:Label>
		</ItemTemplate>
		<EditItemTemplate>
			<asp:TextBox id="txtEditUsed" size="6" runat="server" Text='<%# DataBinder.Eval(Container, "DataItem.Used") %>'></asp:TextBox>
		</EditItemTemplate>
		<FooterTemplate>
			<asp:TextBox id="txtAddUsed" size="6" runat="server"></asp:TextBox>
			<asp:Button id="btnAdd" runat="server" Text="Add" CommandName="Add"></asp:Button>
		</FooterTemplate>
	</asp:TemplateField>

	<asp:CommandField ShowEditButton="True" CancelText="Cancel" DeleteText="Delete" EditText="Edit" UpdateText="Update" HeaderText="Modify"  />
	<asp:CommandField ShowDeleteButton="True" HeaderText="Delete" />
	
	</Columns>
</asp:GridView>
</form>
</body>
</html>