In this article I will explain with an example, how to add and show Serial Number (Row Number) in First Column of Repeater control in ASP.Net using C# and VB.Net.
The Serial Number (Row Number) can be auto generated in the following two ways.
1. Using ItemIndex.
2. Using ItemDataBound event.
 
 

Database

I have made use of the following table Customers with the schema as follows.
Add (Show) Serial Number (Row Number) in ASP.Net Repeater using C# and VB.Net
 
I have already inserted few records in the table.
Add (Show) Serial Number (Row Number) in ASP.Net Repeater using C# and VB.Net
 
Note: You can download the database table SQL by clicking the download link below.
           Download SQL file
 
 
1. Using ItemIndex.
The first technique is using the ItemIndex property which can be used to determine the Index / Serial Number / Row Number of a Repeater Item.
 

HTML Markup

The HTML Markup consists of following controls:
Repeater - For displaying data.
The Repeater consists of following Templates:
HeaderTemplate - The HeaderTemplate consist of a HTML Table.
ItemTemplate – The ItemTemplate consists Label control whose Text property is bound to Container.ItemIndex property and also consists of two Eval function which is Name and Country.
<asp:Repeater ID="Repeater1" runat="server">
    <HeaderTemplate>
        <table cellpadding="0" cellspacing="0">
            <tr>
                <th>Row Number</th>
                <th>Name</th>
                <th>Country</th>
            </tr>
    </HeaderTemplate>
    <ItemTemplate>
        <tr>
            <td><asp:Label ID="lblRowNumber" Text='<%# Container.ItemIndex + 1%>' runat="server" /></td>
            <td><%# Eval("Name")%></td>
            <td><%# Eval("Country")%></td>
        </tr>
    </ItemTemplate>
    <FooterTemplate>
        </table>
    </FooterTemplate>
</asp:Repeater>
 
 

Namespaces

You will need to import the following namespaces.
C#
using System.Data;
using System.Data.SqlClient;
using System.Configuration; 
 
VB.Net
Imports System.Data
Imports System.Data.SqlClient
Imports System.Configuration
 
 

Populating the Repeater control

Inside the Page_Load event handler, the BindRepeater method is called.
Inside the BindRepeater method, first the connection string is read from the Web.Config file.
Note: For more details on how to read connection string from Web.Config file, please refer my article Read or Write Connection Strings in Web.Config file using ASP.Net using C# and VB.Net.
 
Then, the records are fetched from the Customers Table of SQL Server database using SqlDataAdapter and copied to DataTable object using Fill method.
Finally, the DataTable is assigned to the DataSource property of GridView and the GridView is populated.
C#
protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindRepeater();
    }
}
 
private void BindRepeater()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT Name, Country FROM Customers"))
        {
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                cmd.Connection = con;
                sda.SelectCommand = cmd;
                using (DataTable dt = new DataTable())
                {
                    sda.Fill(dt);
                    Repeater1.DataSource = dt;
                    Repeater1.DataBind();
                }
            }
        }
    }
}
 
VB.Net
Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Me.BindRepeater()
    End If
End Sub
 
Private Sub BindRepeater()
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As New SqlConnection(constr)
        Using cmd As New SqlCommand("SELECT Name, Country FROM Customers")
            Using sda As New SqlDataAdapter()
                cmd.Connection = con
                sda.SelectCommand = cmd
                Using dt As New DataTable()
                    sda.Fill(dt)
                    Repeater1.DataSource = dt
                    Repeater1.DataBind()
                End Using
            End Using
        End Using
    End Using
End Sub
 

Screenshot

Add (Show) Serial Number (Row Number) in ASP.Net Repeater using C# and VB.Net
 
 
2. Using ItemDataBound event.
The second technique is using the ItemDataBound event of the Repeater control.
 

HTML Markup

The HTML Markup consists of following controls:
Repeater - For displaying data.
The Repeater consists of following Templates:
HeaderTemplate - The HeaderTemplate consist of a HTML Table.
ItemTemplate – The ItemTemplate consists Label control whose Text property will be set inside the ItemDataBound event handler and also consists of two Eval function which is Name and Country.
<asp:Repeater ID="Repeater2" runat="server" OnItemDataBound="OnItemDataBound">
    <HeaderTemplate>
        <table cellpadding="0" cellspacing="0">
            <tr>
                <th>Row Number</th>
                <th>Name</th>
                <th>Country</th>
            </tr>
    </HeaderTemplate>
    <ItemTemplate>
        <tr>
            <td><asp:Label ID="lblRowNumber" runat="server" /></td>
            <td><%# Eval("Name")%></td>
            <td><%# Eval("Country")%></td>
        </tr>
    </ItemTemplate>
    <FooterTemplate>
        </table>
    </FooterTemplate>
</asp:Repeater>
 
 

Namespaces

You will need to import the following namespaces.
C#
using System.Data;
using System.Data.SqlClient;
using System.Configuration; 
 
VB.Net
Imports System.Data
Imports System.Data.SqlClient
Imports System.Configuration 
 
 

Populating the Repeater control

Inside the Page_Load event handler, the BindRepeater method is called.
Inside the BindRepeater method, first the connection string is read from the Web.Config file.
Note: For more details on how to read connection string from Web.Config file, please refer my article Read or Write Connection Strings in Web.Config file using ASP.Net using C# and VB.Net.
 
Then, the records are fetched from the Customers Table of SQL Server database using SqlDataAdapter and copied to DataTable object using Fill method.
Finally, the DataTable is assigned to the DataSource property of GridView and the GridView is populated.
protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindRepeater();
    }
}
 
private void BindRepeater()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT Name, Country FROM Customers"))
        {
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                cmd.Connection = con;
                sda.SelectCommand = cmd;
                using (DataTable dt = new DataTable())
                {
                    sda.Fill(dt);
                    Repeater2.DataSource = dt;
                    Repeater2.DataBind();
                }
            }
        }
    }
}
VB.Net
Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Me.BindRepeater()
    End If
End Sub
 
Private Sub BindRepeater()
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As New SqlConnection(constr)
        Using cmd As New SqlCommand("SELECT Name, Country FROM Customers")
            Using sda As New SqlDataAdapter()
                cmd.Connection = con
                sda.SelectCommand = cmd
                Using dt As New DataTable()
                    sda.Fill(dt)
                    Repeater2.DataSource = dt
                    Repeater2.DataBind()
                End Using
            End Using
        End Using
    End Using
End Sub
 
 

Displaying Auto generated Row Number in Repeater control using ItemDataBound event

Inside the ItemDataBound event handler, the Label control is searched and then its Text property is set to the ItemIndex of the Repeater Item after incrementing it by one similar to ItemIndex property as ItemIndex is also a zero based index property.
C#
protected void OnItemDataBound(object sender, RepeaterItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
    {
        (e.Item.FindControl("lblRowNumber") as Label).Text = (e.Item.ItemIndex + 1).ToString();
    }
} 
 
VB.Net
Protected Sub OnItemDataBound(ByVal sender As Object, ByVal e As RepeaterItemEventArgs)
    If e.Item.ItemType = ListItemType.Item OrElse e.Item.ItemType = ListItemType.AlternatingItem Then
        CType(e.Item.FindControl("lblRowNumber"), Label).Text = (e.Item.ItemIndex + 1).ToString()
    End If
End Sub
 

Screenshot

Add (Show) Serial Number (Row Number) in ASP.Net Repeater using C# and VB.Net
 
 

Demo

View Demo
 
 

Downloads

Download Code