Populate Bind DropDownList From XML File In Asp.Net

his Example explains how to Populate Or Bind DropDownList With XML File Data In Asp.Net In 3/n Tier Architecture Using C# And VB.

Place one DropdownList on the page.

<asp:DropDownList ID="DropDownList1" 

                  runat="server" 

                  onselectedindexchanged

  ="DropDownList1_SelectedIndexChanged">

XML Data Can be in various formats, i'll use 3 different ones shown below.


Sample 1.

---

   1:  <?xml version="1.0" encoding="utf-8" ?>

   2:  <Employees>

   3:    <Detail>

   4:      <ID>1</ID>

   5:      <Name>Csharp</Name>

   6:    </Detail>

   7:    <Detail>

   8:      <ID>2</ID>

   9:      <Name>AspNet</Name>

  10:    </Detail>

  11:    <Detail>

  12:      <ID>3</ID>

  13:      <Name>Articles</Name>

  14:    </Detail>

  15:  </Employees>

Another format can be

---

   1:  <?xml version="1.0" encoding="utf-8" ?>

   2:  <Employees>

   3:    <Detail ID="1" Name="Csharp"></Detail>

   4:    <Detail ID="2" Name="AspNet"></Detail>

   5:    <Detail ID="3" Name="Articles"></Detail>

   6:  </Employees>

Writing following code in Page_Load event is enough to bind dropdownlist from these types ofXML data.

C#

---

01using System.Data;

02using System.Xml;

03protected void Page_Load(object sender, EventArgs e)

04{

05        DataSet dsXml = new DataSet();

06        dsXml.ReadXml(Server.MapPath("~/XMLFile2.xml"));

07        DropDownList1.DataSource = dsXml;

08        DropDownList1.DataTextField = "Name";

09        DropDownList1.DataValueField = "ID";

10        DropDownList1.DataBind();

11        DropDownList1.AutoPostBack = true;

12}

VB.NET

---

1Protected Sub Page_Load(sender As Object, e As EventArgs)

2 Dim dsXml As New DataSet()

3 dsXml.ReadXml(Server.MapPath("~/XMLFile2.xml"))

4 DropDownList1.DataSource = dsXml

5 DropDownList1.DataTextField = "Name"

6 DropDownList1.DataValueField = "ID"

7 DropDownList1.DataBind()

8 DropDownList1.AutoPostBack = True

9End Sub

If XML format is mix of above two.

---

   1:  <?xml version="1.0" encoding="utf-8" ?>

   2:  <Details>

   3:    <Name ID="1">Amit</Name>

   4:    <Name ID="2">Jain</Name>

   5:    <Name ID="3">Csharp</Name>

   6:    <Name ID="4">AspNet</Name>

   7:    <Name ID="5">Articles</Name>

   8:  </Details>

We need to loop through nodes to fine value of ID attribute.

C#

---

01protected void Page_Load(object sender, EventArgs e)

02    {

03        if (!IsPostBack)

04        {

05            XmlDocument doc = new XmlDocument();

06            doc.Load(Server.MapPath("~/XMLFile.xml"));

07            XmlNodeList list = doc.GetElementsByTagName("Name");

08            foreach (XmlNode node in list)

09            {

10                ListItem lItem = new ListItem(node.InnerText, node.Attributes["ID"].Value);

11                DropDownList1.Items.Add(lItem);

12            }

13            DropDownList1.Items.Insert(0, "--Select--");

14            DropDownList1.SelectedIndex = 0;

15            DropDownList1.AutoPostBack = true;

16        }

17    }

VB

---

01Protected Sub Page_Load(sender As Object, e As EventArgs)

02 If Not IsPostBack Then

03  Dim doc As New XmlDocument()

04  doc.Load(Server.MapPath("~/XMLFile.xml"))

05  Dim list As XmlNodeList = doc.GetElementsByTagName("Name")

06  For Each node As XmlNode In list

07   Dim lItem As New ListItem(node.InnerText, node.Attributes("ID").Value)

08   DropDownList1.Items.Add(lItem)

09  Next

10  DropDownList1.Items.Insert(0, "--Select--")

11  DropDownList1.SelectedIndex = 0

12  DropDownList1.AutoPostBack = True

13 End If

14End Sub

To Bind DropDownList in 3 tier architecture environment, add to new class files in App_Code folder of application and name them DataLayer.cs and BusinessLayer.cs

Write Following code in these class respectively.

Data Access Layer (DAL)

---

01using System.Web;

02using System.Xml;

03public class DataLayer

04{

05 public DataLayer()

06 {

07 }

08    public XmlDocument GetXmlData()

09    {

10        XmlDocument doc = new XmlDocument();

11        doc.Load(HttpContext.Current.Server.MapPath("~/XMLFile.xml"));

12        return doc;

13    }

14}

Business Access Layer (BAL)

---

01using System.Web.UI.WebControls;

02using System.Xml;

03public class BusinessLayer

04{

05 public BusinessLayer()

06 {

07    }

08    public ListItemCollection BindDropDownList()

09    {

10        ListItemCollection ddlItems = new ListItemCollection();

11        DataLayer objDAL = new DataLayer();

12        XmlNodeList list = objDAL.GetXmlData().GetElementsByTagName("Name");

13        foreach (XmlNode node in list)

14        {

15           ListItem item = new ListItem(node.InnerText, node.Attributes["ID"].Value);

16           ddlItems.Add(item);

17 

18        }

19        return ddlItems;

20    }

21}

Write code in Page_Load event of aspx page (Presentation Layer)

---

01protected void Page_Load(object sender, EventArgs e)

02    {

03        if (!IsPostBack)

04        {

05            BusinessLayer objBAL = new BusinessLayer();

06            DropDownList1.DataSource = objBAL.BindDropDownList();

07            DropDownList1.DataBind();

08            DropDownList1.Items.Insert(0, "--Select--");

09            DropDownList1.SelectedIndex = 0;

10            DropDownList1.AutoPostBack = true;

11        }

12    }