When the DataBoundControl has paging enabled, either the SelectMethod should return an IQueryable

Question

User761356933 posted

I have something odd going on. 

This was working fine, until I added an update method to my code behind. I don't understand what its changed.

My select method does return iqueryable supplier - but when I put I breakpoint it seems it never even enters the select method. Can someone help me out here as I have been stuck with this for days now.

Error:

When the DataBoundControl has paging enabled, either the SelectMethod should return an IQueryable<ItemType> or should have all these mandatory parameters : int startRowIndex, int maximumRows, out int totalRowCount

Select method:

// The return type can be changed to IEnumerable, however to support
        // paging and sorting, the following parameters must be added:
        //     int maximumRows
        //     int startRowIndex
        //     out int totalRowCount
        //     string sortByExpression
        public IQueryable<supplier> GridView1_GetData()
        {

            SupplierDBModel context = new SupplierDBModel();
            return (from s in context.suppliers
                    select s).AsQueryable();
        }

Grid:

                <asp:GridView ID="GridView1" CssClass="table table-hover table-striped" SelectMethod="GridView1_GetData" DeleteMethod="GridView1_DeleteItem" UpdateMethod="GridView1_UpdateItem" AllowPaging="True"  AllowSorting="True" ItemType="PrincePortalWeb.Models.supplier" runat="server" AutoGenerateEditButton="True" AutoGenerateDeleteButton="True"              
            AutoGenerateSelectButton="True"  AutoGenerateColumns="False" ShowFooter="True"  DataKeyNames="supplierid" >
                                     <Columns>
                         <asp:BoundField DataField="supplierid" HeaderText="ID" />
                        <asp:BoundField ApplyFormatInEditMode="True" DataField="suppliername" HeaderText="Customer">
                        <HeaderStyle Font-Bold="True" HorizontalAlign="Center" />
                        <ItemStyle HorizontalAlign="Center" />
                        </asp:BoundField>
                        <asp:BoundField DataField="status" HeaderText="Status">
                        <HeaderStyle Font-Bold="True" HorizontalAlign="Center" />
                        <ItemStyle HorizontalAlign="Center" />
                        </asp:BoundField>
                        <asp:BoundField DataField="whencompliant.date" HeaderText="When Compliant" />
                        <asp:BoundField DataField="reviewdate.date" HeaderText="Review Date" />
                        <asp:BoundField DataField="lastreviewedby" HeaderText="Reviewed By" />
                        <asp:BoundField DataField="webstatus" HeaderText="Portal Status" />
                    </Columns>

Supplier context and class:

    public partial class SupplierDBModel : DbContext
    {




        public SupplierDBModel()
            : base("name=SupplierDBModel")
        {


            // Database.SetInitializer(new MigrateDatabaseToLatestVersion<SupplierDBModel, EF6Console.Migrations.Configuration>());


        }

        public virtual DbSet<supplier> suppliers { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
        }

    }

        public partial class supplier 
        {


            public int supplierid { get; set; }

            [Required]
            [StringLength(50)]
            public string suppliername { get; set; }

            [StringLength(50)]
            public string address1 { get; set; }

            [StringLength(50)]
            public string county { get; set; }

            [StringLength(50)]
            public string country { get; set; }

            [StringLength(50)]
            public string telephone { get; set; }

            [StringLength(50)]
            public string address2 { get; set; }

            [StringLength(11)]
            public string postcode { get; set; }

            [StringLength(20)]
            public string webstatus { get; set; }

           
            public status status { get; set; }

            [StringLength(50)]
            public string LastreviewedBy { get; set; }

            [Column(TypeName = "datetime2")]
            public DateTime Whencompliant { get; set; }
            [Column(TypeName = "datetime2")]
            public DateTime Reviewdate { get; set; }



        }

    public enum status
    {
        Compliant,
        In_Progress,
        Not_Started,


    }

    }

Thank you

Answer 1

User761356933 posted

OK

I have found just having this in the code behind file throws the error. If I remove this method it works fine. I have put a breakpoint on this method and it doesn't enter it on load. So whats happening here? can anyone shed some light on this, I want to understand.

If I comment this out its fine:

        protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
        {

            GridViewRow row = GridView1.Rows[e.NewEditIndex];

            TextBox txtName = row.FindControl("txtSupplierName") as TextBox;

            using (SupplierDBModel context = new SupplierDBModel())
            {
                int supplierID = Convert.ToInt32(GridView1.DataKeys[e.NewEditIndex].Value);
                supplier suppobj = context.suppliers.First(s => s.supplierid == supplierID);
                suppobj.suppliername = txtName.Text.Trim();
                context.SaveChanges();

            }

        }

Answer 2

User1724605321 posted

Hi BluSky28,

That is quite strange since the gridview even doesn't have the RowEditing event registered . In my opinion , it won't be the reason which leads to your error , it won't fire since it is not registered . Please double check your codes and try to find whether any other codes affect in this scenario .

Best Regards,

Nan Yu