Merge GridView Cells

In this example i am going to describe how to Merge GridView Cells Or Columns In Gridview Rows Using C# and VB.NET in ASP.NET Containing Same Data or content. For this i m using DataBound Event of gridview, counting total rows and then checking each cells value against value of same cell in previous row and then setting the RowSpan of cells.

Merge GridView Cells Or Columns

For this i have created a table containing Counties ,states and respective cities and country and state cells / columns are merged in rows having same country or states.

Html source of the page look like this 

<asp:GridView ID="GridView1" runat="server" 
    AutoGenerateColumns="False"  
    BorderStyle="None" BorderWidth="1px" CellPadding="4" 
    GridLines="Horizontal" ForeColor="Black" 
    Height="119px" DataSourceID="SqlDataSource1" 
    OnDataBound="GridView1_DataBound1"> 
            <Columns>
            <asp:BoundField DataField="Country" 
                            HeaderText="Country" 
                            SortExpression="Country" />
            <asp:BoundField DataField="State" 
                            HeaderText="State" 
                            SortExpression="State" />
            <asp:BoundField DataField="City" 
                            HeaderText="City" 
                            SortExpression="City" />
        </Columns>
</asp:GridView>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" 
ConnectionString="<%$ ConnectionStrings:ConnectionString %>"
SelectCommand="SELECT [Country], [State], [City] 
               FROM [Details] ORDER BY [State]">
</asp:SqlDataSource>
C# code behind
protected void GridView1_DataBound1(object sender, EventArgs e)
{
  for (int rowIndex = GridView1.Rows.Count - 2; 
                                     rowIndex >= 0; rowIndex--)
  {
    GridViewRow gvRow = GridView1.Rows[rowIndex];
    GridViewRow gvPreviousRow = GridView1.Rows[rowIndex + 1];
    for (int cellCount = 0; cellCount < gvRow.Cells.Count; 
                                                  cellCount++)
    {
     if (gvRow.Cells[cellCount].Text == 
                            gvPreviousRow.Cells[cellCount].Text)
     {
       if (gvPreviousRow.Cells[cellCount].RowSpan < 2)
       {
         gvRow.Cells[cellCount].RowSpan = 2;
       }
       else
       {
        gvRow.Cells[cellCount].RowSpan = 
            gvPreviousRow.Cells[cellCount].RowSpan + 1;
       }
       gvPreviousRow.Cells[cellCount].Visible = false;
    }
   }
 }
}
VB.NET code behind
Protected Sub GridView1_DataBound1
           (ByVal sender As Object, ByVal e As EventArgs)

For rowIndex As Integer = GridView1.Rows.Count - 2 To 0 Step -1
    Dim gvRow As GridViewRow = GridView1.Rows(rowIndex)
    Dim gvPreviousRow As GridViewRow = GridView1.Rows(rowIndex + 1)
    For cellCount As Integer = 0 To gvRow.Cells.Count - 1
    If gvRow.Cells(cellCount).Text = 
                         gvPreviousRow.Cells(cellCount).Text Then
    If gvPreviousRow.Cells(cellCount).RowSpan < 2 Then
    gvRow.Cells(cellCount).RowSpan = 2
    Else
    gvRow.Cells(cellCount).RowSpan = 
                       gvPreviousRow.Cells(cellCount).RowSpan + 1
    End If
    gvPreviousRow.Cells(cellCount).Visible = False
    End If
    Next
  Next
End Sub

Happy Coding !!