Update Data in DataList Using Template With EntityFramework in ASP.Net 4.0

Introduction

This article provides an example of how to update a DataList in ASP.Net. This code example updates data using the Entity Framework. Updating data in a DataList is very easy in ASP.Net, I have used the Entity Framework to Insert, Update and Delete data from a DataList.

Background

For example, a DataList containing a Label, TextBox and Button as a template for displaying and raising events. The DataList in my page is as given below, to do this using the code Drag one DataList Control from a Toolbox and declare their ItemTemplate as given below.

HTML Code

<p class=" "style="margin-bottom: 0.0001pt;"><asp:DataListID="DataList1" runat="server" width="100%"
oncancelcommand="DataList1_CancelCommand" oneditcommand="DataList1_EditCommand"
onitemcommand="DataList1_ItemCommand" onitemdatabound="DataList1_ItemDataBound"
onupdatecommand="DataList1_UpdateCommand">
<HeaderTemplate>
<table width="100%">
</HeaderTemplate>
<ItemTemplate>
<tr>
<td style="width:30%">Address1:</td>
<td><%#Eval("Address1")%></td>
</tr>
<tr>
<td>Address2:</td>
<td><%#Eval("Address2")%></td>
</tr>
<tr>
<td style="width:30%">City:</td>
<td><%#Eval("City")%></td>
</tr>
<tr>
<td>State:</td>
<td><%#Eval("State")%></td>
</tr>
<tr>
<td>Pin Code:</td>
<td><%#Eval("PIN")%></td>
</tr>
<tr>
<td>
</td>
<td><asp:LinkButton ID="LinkButton1" runat="server" CommandName="Edit">Edit</asp:LinkButton></td>
</tr>
</ItemTemplate>
<EditItemTemplate>
<tr>
<td style="width:10%">Address1:</td>
<td><asp:TextBox ID="txtAdd1" runat="server" Width="200px" Text='<%#Eval("Address1") %>'></asp:TextBox></td>
</tr>
<tr>
<td>Address2:</td>
<td><asp:TextBox ID="txtAdd2" runat="server" Width="200px" Text='<%#Eval("Address2") %>'></asp:TextBox></td>
</tr>
<tr>
<td style="width:30%">City:</td>
<td><asp:TextBox ID="txtCity" runat="server" Width="200px" Text='<%#Eval("City") %>'></asp:TextBox></td>
</tr>
<tr>
<td>State:</td>
<td><asp:TextBox ID="txtState" runat="server" Width="200px" Text='<%#Eval("State") %>'></asp:TextBox></td>
</tr>
<tr>
<td>Pin Code:</td>
<td><asp:TextBox ID="txtPin" runat="server" Text='<%#Eval("PIN") %>'></asp:TextBox>
<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server"
ErrorMessage="Invalide Pin" ControlToValidate="txtPin"
ValidationExpression="\d{6}">*</asp:RegularExpressionValidator>
</td>
</tr>
<tr>
<td>
</td>
<td><asp:Button ID="btnsave" runat="server" Text="Update" EnableViewState="False"
Font-Italic="True" CommandName="Update"></asp:Button>
<asp:Button ID="btncancel" runat="server" Text="Cancel" EnableViewState="False" Font-Italic="True" CommandName="Cancel"></asp:Button>
</td>
</tr>
</EditItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:DataList>

On the page load event bind your DataList with the database. I have used the Entity Framework to bind to the database as in the following:

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        if (Request.QueryString["id"] == null)
        {
            using (OCSEntities ocs = new OCSEntities())
            {
                ocs.Connection.Open();
                DataList1.DataSource = ocs.Addresses.Where(item => item.UID == SessionManager.Current.CurrentUser.ID).ToList();
                DataList1.DataBind();
            }
        }
        else
        {
            DataList1.Visible = false;
            pnlnew.Visible = true;
        }
    }
}

Use an ItemCommand Event to specify the Edit item index of the DataList.

For example:

protected void DataList1_ItemCommand(object source, DataListCommandEventArgs e)
{
    if (e.CommandName == "Edit")
    {
        DataList1.EditItemIndex = 0;
    }
}

Again, rebind your DataList to a database table in the editcommand event of the DataList control:

protected void DataList1_EditCommand(object source, DataListCommandEventArgs e)
{
    //DataList1.EditItemIndex = 0;
    using (OCSEntities ocs = new OCSEntities())
    {
        ocs.Connection.Open();
        DataList1.DataSource = ocs.Addresses.Where(item => item.UID == SessionManager.Current.CurrentUser.ID).ToList();
        DataList1.DataBind();
    }
}

Use the updatecommand event to update your database as in the following:

protected void DataList1_UpdateCommand(object source, DataListCommandEventArgs e)
{
    if (e.Item.ItemType == ListItemType.EditItem)
    {
        using (OCSEntities ocs = new OCSEntities())
        {
            ocs.Connection.Open();
            OCSModel.Address ad = ocs.Addresses.Where(item => item.UID == SessionManager.Current.CurrentUser.ID).First();
            ad.Address1 = ((TextBox)e.Item.FindControl("txtAdd1")).Text;
            ad.Address2 = ((TextBox)e.Item.FindControl("txtAdd2")).Text;
            ad.City = ((TextBox)e.Item.FindControl("txtCity")).Text;
            ad.State = ((TextBox)e.Item.FindControl("txtState")).Text;
            ad.PIN = ((TextBox)e.Item.FindControl("txtPin")).Text;
            ocs.SaveChanges();
            ocs.AcceptAllChanges();
        }
        DataList1.EditItemIndex = -1;
        using (OCSEntities ocs = new OCSEntities())
        {
            ocs.Connection.Open();
            DataList1.DataSource = ocs.Addresses.Where(item => item.UID == SessionManager.Current.CurrentUser.ID).ToList();
            DataList1.DataBind();
        }
    }
}

Summary

In the preceding example, we demonstrated how to use a template in the DataList box and update the database using the Entity Framework.