I have a button to add a new record into the grid. When I click the add button I want to add a record into the store and then start editing the record in the grid...

       function doAdd() {
            var rec = App.Store1.add({company: 'New Company'})[0];
            App.CellEditing1.startEdit(rec, App.GridPanel1.columns[0]);
This works fine if there is no IDProperty set on the Model....it has the desired effect (record added then first column of newly added row has the editor active).

However if you add an IDProperty to the model. It sets the editor but quickly goes back to the previously selected item.

Working Example
<%@ Page Language="C#" %>

<%@ Register Assembly="Ext.Net" Namespace="Ext.Net" TagPrefix="ext" %>
<script runat="server">
    protected void Page_Load(object sender, EventArgs e)
        Store1.DataSource = Data();

    public object[] Data()
            return new object[]
                new object[] { 1, "3m Co", 71.72, 0.02, 0.03, "9/1 12:00am" },
                new object[] { 2, "Alcoa Inc", 29.01, 0.42, 1.47, "9/1 12:00am" },
                new object[] { 3,"Altria Group Inc", 83.81, 0.28, 0.34, "9/1 12:00am" },
                new object[] { 4,"American Express Company", 52.55, 0.01, 0.02, "9/1 12:00am" },
                new object[] { 5, "American International Group, Inc.", 64.13, 0.31, 0.49, "9/1 12:00am" }

<!DOCTYPE html>

<head id="Head1" runat="server">
    <title>Simple Array Grid - Ext.NET Examples</title>
    <link href="/resources/css/examples.css" rel="stylesheet" />    

        .x-grid-row-over .x-grid-cell-inner {
            font-weight : bold;

        var template = '<span style="color:{0};">{1}</span>';

        var change = function (value) {
            return Ext.String.format(template, (value > 0) ? "green" : "red", value);

        var pctChange = function (value) {
            return Ext.String.format(template, (value > 0) ? "green" : "red", value + "%");
    <ext:ResourceManager ID="ResourceManager1" runat="server" Theme="Neptune" ScriptMode="Debug"/>
    <h1>Simple Array Grid</h1>
    <ext:Button runat="server" Text="Show and Select">
            <Click Handler="doAdd();" />

    <script type="text/javascript">
        function doAdd() {
            var rec = App.Store1.add({company: 'New Company'})[0];
            App.CellEditing1.startEdit(rec, App.GridPanel1.columns[0]);
        Title="Array Grid" 
            <ext:Store ID="Store1" runat="server">
                    <ext:Model ID="Model1" runat="server">
                            <ext:ModelField Name="companyId" Type="Int" />
                            <ext:ModelField Name="company" />
                            <ext:ModelField Name="price" Type="Float" />
                            <ext:ModelField Name="change" Type="Float" />
                            <ext:ModelField Name="pctChange" Type="Float" />
                            <ext:ModelField Name="lastChange" Type="Date" DateFormat="M/d hh:mmtt" />
                <ext:Column ID="Column1" runat="server" Text="Company" DataIndex="company" Flex="1">
                        <ext:TextField runat="server" />
                <ext:Column ID="Column2" runat="server" Text="Price" DataIndex="price">                  
                    <Renderer Format="UsMoney" />
                <ext:Column ID="Column3" runat="server" Text="Change" DataIndex="change">
                    <Renderer Fn="change" />
                <ext:Column ID="Column4" runat="server" Text="Change" DataIndex="pctChange">
                    <Renderer Fn="pctChange" />
                <ext:DateColumn ID="DateColumn1" runat="server" Text="Last Updated" DataIndex="lastChange" />
            <ext:CellEditing ID="CellEditing1" runat="server" ClicksToEdit="1" />
            <ext:Toolbar ID="Toolbar1" runat="server">
                    <ext:Button ID="Button1" runat="server" Text="Print" Icon="Printer" Handler="this.up('grid').print();" />

To make it not work change the Model declaration to this

     <ext:Model ID="Model1" runat="server" IDProperty="companyId">