Perform Outer Join in Linq query using C# and VB.Net in ASP.Net

Hi SUJAYS,

Please refer below sample.

HTML

<asp:GridView runat="server" ID="gvCustomers" AutoGenerateColumns="false">
    <Columns>
        <asp:BoundField DataField="CustomerId" HeaderText="CustomerId" />
        <asp:BoundField DataField="ContactName" HeaderText="ContactName" />
        <asp:BoundField DataField="ShipCity" HeaderText="ShipCity" />
        <asp:BoundField DataField="OrderId" HeaderText="OrderId" />
    </Columns>
</asp:GridView>

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        NorthwindEntities enity = new NorthwindEntities();
        var result = from c in enity.Customers
                        join o in enity.Orders on c.CustomerID equals o.CustomerID into ps
                        from o in ps.DefaultIfEmpty()
                        select new
                        {
                            ContactName = c.CompanyName,
                            CustomerID = c.CustomerID,
                            ShipCity = o.ShipCity,
                            OrderId = (o.OrderID == null ? 0 : o.OrderID)
                        };
        this.gvCustomers.DataSource = result.ToList().Take(5);
        this.gvCustomers.DataBind();
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Dim enity As NorthwindEntities = New NorthwindEntities()
        Dim result = From c In enity.Customers
                     Group Join o In enity.Orders On c.CustomerID Equals o.CustomerID
                     Into ps = Group From o In ps.DefaultIfEmpty()
        Select New With {
                .ContactName = c.CompanyName,
                .CustomerID = c.CustomerID,
                .ShipCity = o.ShipCity}
        Me.gvCustomers.DataSource = result.ToList().Take(5)
        Me.gvCustomers.DataBind()
    End If
End Sub

Screenshot