In this article I will explain how to implement GridView Grouping i.e. group similar GridView Rows in ASP.Net using C# and VB.Net.
You can also read some other interesting articles on GridView:-
 
 
Database
Here I am making use of Microsoft’s Northwind Database. You can download it from here
Download and install Northwind Database
 
HTML Markup
The HTML Markup consists of an ASP.Net GridView with three columns populated from the Customers Table of the Northwind Database.
<asp:GridView ID="GridView1" HeaderStyle-BackColor="#3AC0F2" HeaderStyle-ForeColor="White"
    runat = "server" AutoGenerateColumns="false" OnDataBound="OnDataBound">
    <Columns>
        <asp:BoundField DataField="Country" HeaderText="Country" ItemStyle-Width="150" />
        <asp:BoundField DataField="City" HeaderText="City" ItemStyle-Width="150" />
        <asp:BoundField DataField="ContactName" HeaderText="Name" ItemStyle-Width="150" />
    </Columns>
</asp:GridView>

You will notice that we have specified the OnDataBound event of the GridView, this event will be used to write the logic for merging the GridView Columns or Cells.
 
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
 
 
Binding the GridView
Below is the code to populate the ASP.Net GridView with the records from the Customers Table of the Northwind Database.
C#
protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        DataTable dt = new DataTable();
        GridView1.DataSource = GetData("SELECT ContactName, Country, City FROM Customers GROUP BY Country, City, ContactName");
        GridView1.DataBind();
    }
}
private DataTable GetData(string query)
{
    DataTable dt = new DataTable();
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand(query))
        {
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                cmd.CommandType = CommandType.Text;
                cmd.Connection = con;
                sda.SelectCommand = cmd;
                sda.Fill(dt);
            }
        }
        return dt;
    }
}
 
VB.Net
Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Dim dt As New DataTable()
        GridView1.DataSource = GetData("SELECT ContactName, Country, City FROM Customers GROUP BY Country, City, ContactName")
        GridView1.DataBind()
    End If
End Sub
 
Private Function GetData(query As String) As DataTable
    Dim dt As New DataTable()
    Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As New SqlConnection(constr)
        Using cmd As New SqlCommand(query)
            Using sda As New SqlDataAdapter()
                cmd.CommandType = CommandType.Text
                cmd.Connection = con
                sda.SelectCommand = cmd
                sda.Fill(dt)
            End Using
        End Using
        Return dt
    End Using
End Function
 
Merge GridView Cells or Columns in a Row in ASP.Net using C# VB.Net
 
 
Merge Common Cells or Columns in a Row in ASP.Net GridView
The OnDataBound event of the GridView is executed after the GridView is populated with records. Here a reverse loop is executed over the GridView Rows and then the common Cells are identified and merged into single cell.
C#
protected void OnDataBound(object sender, EventArgs e)
{
    for (int i = GridView1.Rows.Count - 1; i > 0; i--)
    {
        GridViewRow row = GridView1.Rows[i];
        GridViewRow previousRow = GridView1.Rows[i - 1];
        for (int j = 0; j < row.Cells.Count; j++)
        {
            if (row.Cells[j].Text == previousRow.Cells[j].Text)
            {
                if (previousRow.Cells[j].RowSpan == 0)
                {
                    if (row.Cells[j].RowSpan == 0)
                    {
                        previousRow.Cells[j].RowSpan += 2;
                    }
                    else
                    {
                        previousRow.Cells[j].RowSpan = row.Cells[j].RowSpan + 1;
                    }
                    row.Cells[j].Visible = false;
                }
            }
        }
    }
}
 
VB.Net
Protected Sub OnDataBound(sender As Object, e As EventArgs)
    For i As Integer = GridView1.Rows.Count - 1 To 1 Step -1
        Dim row As GridViewRow = GridView1.Rows(i)
        Dim previousRow As GridViewRow = GridView1.Rows(i - 1)
        For j As Integer = 0 To row.Cells.Count - 1
            If row.Cells(j).Text = previousRow.Cells(j).Text Then
                If previousRow.Cells(j).RowSpan = 0 Then
                    If row.Cells(j).RowSpan = 0 Then
                        previousRow.Cells(j).RowSpan += 2
                    Else
                        previousRow.Cells(j).RowSpan = row.Cells(j).RowSpan + 1
                    End If
                    row.Cells(j).Visible = False
                End If
            End If
        Next
    Next
End Sub
 
 
Merge GridView Cells or Columns in a Row in ASP.Net using C# VB.Net
 
Demo
View Demo
 
Downloads