Nested GridView Example In Asp.Net With Expand Collapse

This example shows how to create Nested GridView In Asp.Net Using C# And VB.NET With Expand Collapse Functionality.
I have used JavaScript to Create Expandable Collapsible Effect by displaying Plus Minus image buttons.

Customers and Orders Table of Northwind Database are used to populate nested GridViews.

Drag and place SqlDataSource from toolbox on aspx page and configure and choose it as datasource from smart tags

Go to HTML source of page and add 2 TemplateField in <Columns>, one as first column and one as last column of gridview.

Place another grid in last templateField column.

Markup of page after adding both templatefields will like as shown below.



HTML SOURCE

---

   1:  <asp:GridView ID="gvMaster" runat="server" 

   2:                AllowPaging="True" 

   3:                AutoGenerateColumns="False" 

   4:                DataKeyNames="CustomerID" 

   5:                DataSourceID="SqlDataSource1" 

   6:                onrowdatabound="gvMaster_RowDataBound">

   7:  <Columns>

   8:  <asp:TemplateField>

   9:      <ItemTemplate>

  10:      <a href="javascript:collapseExpand('customerID-

  11:               <%# Eval("CustomerID") %>');">

  12:      <img id="imagecustomerID-<%# Eval("CustomerID") %>" 

  13:           alt="Click to show/hide orders" 

  14:           border="0" src="plus.png" /></a>

  15:      </ItemTemplate>

  16:  </asp:TemplateField>

  17:  <asp:BoundField DataField="CustomerID" 

  18:                  HeaderText="CustomerID"/>

  19:  <asp:BoundField DataField="CompanyName" 

  20:                  HeaderText="CompanyName"/>

  21:   

  22:  <asp:TemplateField>

  23:  <ItemTemplate>

  24:  <tr><td colspan="100%">

  25:  <div id="customerID-<%# Eval("CustomerID") %>" 

  26:       style="display:none;

  27:       position:relative;left:25px;">

  28:       

  29:  <asp:GridView ID="nestedGridView" runat="server" 

  30:                AutoGenerateColumns="False" 

  31:                DataKeyNames="OrderID">

  32:  <Columns>

  33:  <asp:BoundField DataField="OrderID" HeaderText="OrderID"/>

  34:  <asp:BoundField DataField="OrderDate" HeaderText="OrderDate"/>

  35:  <asp:BoundField DataField="Freight" HeaderText="Freight"/>

  36:  </Columns>

  37:  </asp:GridView>

  38:  </div>

  39:  </td></tr>

  40:  </ItemTemplate>

  41:  </asp:TemplateField>

  42:  </Columns>

  43:  </asp:GridView>

  44:   

  45:  <asp:SqlDataSource ID="SqlDataSource1" runat="server" 

  46:  ConnectionString="<%$ ConnectionStrings:ConnectionString %>" 

  47:  SelectCommand="SELECT [CustomerID], [CompanyName] 

  48:                 FROM [Customers]">

  49:  </asp:SqlDataSource>

Add following JavaScript in head section of page.

---

Write following code in RowDataBound Event of parent Grid to populate nested gridview.

C#

---

protected void gvMaster_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            string customerID = Convert.ToString(DataBinder.Eval(e.Row.DataItem, "CustomerID"));
            GridView gvChild = (GridView)e.Row.FindControl("nestedGridView");
            SqlDataSource gvChildSource = new SqlDataSource();
            gvChildSource.ConnectionString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
            gvChildSource.SelectCommand = "SELECT [OrderID], [OrderDate],[Freight] FROM [Orders] WHERE [CustomerID] = '" + customerID + "'";
            gvChild.DataSource = gvChildSource;
            gvChild.DataBind();
        }
    }

VB.NET

---

Protected Sub gvMaster_RowDataBound(sender As Object, e As GridViewRowEventArgs)
 If e.Row.RowType = DataControlRowType.DataRow Then
  Dim customerID As String = Convert.ToString(DataBinder.Eval(e.Row.DataItem, "CustomerID"))
  Dim gvChild As GridView = DirectCast(e.Row.FindControl("nestedGridView"), GridView)
  Dim gvChildSource As New SqlDataSource()
  gvChildSource.ConnectionString = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString
  gvChildSource.SelectCommand = "SELECT [OrderID], [OrderDate],[Freight] FROM [Orders] WHERE [CustomerID] = '" + customerID + "'"
  gvChild.DataSource = gvChildSource
  gvChild.DataBind()
 End If
End Sub

Build and run the application to test GridView Inside Grid.

Download Sample Code