ASP.Net Error: Unable to cast object of type System.Data.DataTable to type System.Data.DataView

Hi lisamaclea,

Check this sample. now take its reference and correct your code.

Database

For this example I have used of Northwind database that you can download using the link given below.

Download Northwind Database

HTML

<asp:GridView ID="gvCustomers" runat="server" AutoGenerateColumns="False" DataKeyNames="CustomerID"
    AllowPaging="true" OnPageIndexChanging="gvCustomers_PageIndexChanging" PageSize="10">
    <Columns>
        <asp:BoundField DataField="CustomerID" HeaderText="CustomerID" />
        <asp:BoundField DataField="ContactName" HeaderText="ContactName" />
        <asp:BoundField DataField="City" HeaderText="City" />
        <asp:BoundField DataField="Country" HeaderText="Country" />
    </Columns>
</asp:GridView>
<asp:Label ID="lblCount" Text="" runat="server" />

Namespaces

C#

using System.Configuration;
using System.Data;
using System.Data.SqlClient;

VB.Net

Imports System.Configuration
Imports System.Data
Imports System.Data.SqlClient

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindCustomers();
    }
}

private void BindCustomers()
{
    using (SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ConnectionString))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT CustomerID,ContactName,City,Country FROM Customers", con))
        {
            cmd.CommandType = CommandType.Text;
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                sda.SelectCommand = cmd;
                DataTable dt = new DataTable();
                sda.Fill(dt);
                this.gvCustomers.DataSource = dt;
                this.gvCustomers.DataBind();
                int TotalRecords = ((System.Data.DataTable)gvCustomers.DataSource).Rows.Count;
                int CurrentRecordStart = gvCustomers.PageIndex * gvCustomers.PageSize + 1;
                int CurrentRecordEnd = gvCustomers.PageIndex * gvCustomers.PageSize + gvCustomers.Rows.Count;
                lblCount.Text = string.Format("Displaying {0} to {1} of {2} records found", CurrentRecordStart, CurrentRecordEnd, TotalRecords);
            }
        }
    }
}

protected void gvCustomers_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
    gvCustomers.PageIndex = e.NewPageIndex;
    this.BindCustomers();
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Me.BindCustomers()
    End If
End Sub

Private Sub BindCustomers()
    Using con As SqlConnection = New SqlConnection(ConfigurationManager.ConnectionStrings("NorthwindConnectionString").ConnectionString)
        Using cmd As SqlCommand = New SqlCommand("SELECT CustomerID,ContactName,City,Country FROM Customers", con)
            cmd.CommandType = CommandType.Text
            Using sda As SqlDataAdapter = New SqlDataAdapter()
                sda.SelectCommand = cmd
                Dim dt As DataTable = New DataTable()
                sda.Fill(dt)
                Me.gvCustomers.DataSource = dt
                Me.gvCustomers.DataBind()
                Dim TotalRecords As Integer = (CType(gvCustomers.DataSource, System.Data.DataTable)).Rows.Count
                Dim CurrentRecordStart As Integer = gvCustomers.PageIndex * gvCustomers.PageSize + 1
                Dim CurrentRecordEnd As Integer = gvCustomers.PageIndex * gvCustomers.PageSize + gvCustomers.Rows.Count
                lblCount.Text = String.Format("Displaying {0} to {1} of {2} records found", CurrentRecordStart, CurrentRecordEnd, TotalRecords)
            End Using
        End Using
    End Using
End Sub

Protected Sub gvCustomers_PageIndexChanging(ByVal sender As Object, ByVal e As GridViewPageEventArgs)
    gvCustomers.PageIndex = e.NewPageIndex
    Me.BindCustomers()
End Sub

Screenshot