You may consider a StringFilter override like in the code sample below:
<%@ Page Language="C#" %>
<%@ Register Assembly="Ext.Net" Namespace="Ext.Net" TagPrefix="ext" %>
<%@ Import Namespace="System.Data" %>
<script runat="server">
private DataTable TestData
{
get
{
var updated = new DateTime(2013, 01, 20);
var addDays = 1;
var dataTable = new DataTable();
dataTable.Columns.AddRange(new DataColumn[] {
new DataColumn { ColumnName = "company", DataType = typeof(System.String) },
new DataColumn { ColumnName = "industry", DataType = typeof(System.String) },
new DataColumn { ColumnName = "price", DataType = typeof(System.Double) },
new DataColumn { ColumnName = "change", DataType = typeof(System.Double) },
new DataColumn { ColumnName = "pctChange", DataType = typeof(System.Double) },
new DataColumn { ColumnName = "lastChange", DataType = typeof(System.DateTime) },
new DataColumn { ColumnName = "visible", DataType = typeof(System.Boolean) },
});
var dataArray = new object[]
{
new object[] { "3m Co", "Conglomerates", 71.72, 0.02, 0.03, updated.AddDays(addDays++), true },
new object[] { "Alcoa Inc", "Basic Materials", 29.01, 0.42, 1.47, updated.AddDays(addDays++), true },
new object[] { "Altria Group Inc", "Consumer Goods", 83.81, 0.28, 0.34, updated.AddDays(addDays++), true },
new object[] { "American Express Company", "Financial", 52.55, 0.01, 0.02, updated.AddDays(addDays++), true },
new object[] { "American International Group, Inc.", "Financial", 64.13, 0.31, 0.49, updated.AddDays(addDays++), false },
new object[] { "AT&T Inc.", "Technology", 31.61, -0.48, -1.54, updated.AddDays(addDays++), false },
new object[] { "Boeing Co.", "Industrial", 75.43, 0.53, 0.71, updated.AddDays(addDays++), false },
new object[] { "Caterpillar Inc.", "Industrial", 67.27, 0.92, 1.39, updated.AddDays(addDays++), false },
new object[] { "Citigroup, Inc.", "Financial", 49.37, 0.02, 0.04, updated.AddDays(addDays++), false },
new object[] { "E.I. du Pont de Nemours and Company", "Basic Materials", 40.48, 0.51, 1.28, updated.AddDays(addDays++), false },
new object[] { "Exxon Mobil Corp", "Energy", 68.1, -0.43, -0.64, updated.AddDays(addDays++), true },
new object[] { "General Electric Company", "Industrial", 34.14, -0.08, -0.23, updated.AddDays(addDays++), true },
new object[] { "General Motors Corporation", "Consumer", 30.27, 1.09, 3.74, updated.AddDays(addDays++), true },
new object[] { "Hewlett-Packard Co.", "Technology", 36.53, -0.03, -0.08, updated.AddDays(addDays++), true },
new object[] { "Honeywell Intl Inc", "Industrial", 38.77, 0.05, 0.13, updated.AddDays(addDays++), true },
new object[] { "Intel Corporation", "Technology", 19.88, 0.31, 1.58, updated.AddDays(addDays++), false },
new object[] { "International Business Machines", "Technology", 81.41, 0.44, 0.54, updated.AddDays(addDays++), false },
new object[] { "Johnson & Johnson", "Consumer", 64.72, 0.06, 0.09, updated.AddDays(addDays++), false },
new object[] { "JP Morgan & Chase & Co", "Financial", 45.73, 0.07, 0.15, updated.AddDays(addDays++), false },
new object[] { "McDonald\"s Corporation", "Consumer", 36.76, 0.86, 2.40, updated.AddDays(addDays++), false },
new object[] { "Merck & Co., Inc.", "Consumer", 40.96, 0.41, 1.01, updated.AddDays(addDays++), true },
new object[] { "Microsoft Corporation", "Technology", 25.84, 0.14, 0.54, updated.AddDays(addDays++), false },
new object[] { "Pfizer Inc", "Consumer", 27.96, 0.4, 1.45, updated.AddDays(addDays++), false},
new object[] { "The Coca-Cola Company", "Consumer", 45.07, 0.26, 0.58, updated.AddDays(addDays++), true },
new object[] { "The Home Depot, Inc.", "Consumer", 34.64, 0.35, 1.02, updated.AddDays(addDays++), true },
new object[] { "The Procter & Gamble Company", "Consumer", 61.91, 0.01, 0.02, updated.AddDays(addDays++), true },
new object[] { "United Technologies Corporation", "Industrial", 63.26, 0.55, 0.88, updated.AddDays(addDays++), true },
new object[] { "Verizon Communications", "Communications", 35.57, 0.39, 1.11, updated.AddDays(addDays++), true },
new object[] { "Wal-Mart Stores, Inc.", "Consumer", 45.45, 0.73, 1.63, updated.AddDays(addDays++), true }
};
foreach (object[] row in dataArray)
{
dataTable.LoadDataRow(row, true);
}
return dataTable;
}
}
protected void Page_Load(object sender, EventArgs e)
{
if (!X.IsAjaxRequest)
{
this.Store1.DataSource = this.TestData;
this.Store1.DataBind();
}
}
</script>
<!DOCTYPE html>
<html>
<head id="Head1" runat="server">
<title>Local Data Paging - Ext.NET Examples</title>
<script type="text/javascript">
if (Ext.ux.grid.filter) {
Ext.ux.grid.filter.StringFilter.override({
init: function (config) {
Ext.applyIf(config, {
// Set this property to "true" for default behavior
// You also have to deactivate the filter manually after clearing the filter input box now
enableKeyEvents: false,
labelCls: 'ux-rangemenu-icon ' + this.iconCls,
hideEmptyLabel: false,
labelSeparator: '',
labelWidth: 29
});
if (!config.listeners) {
config.listeners = {};
}
Ext.applyIf(config.listeners, {
scope: this,
keyup: this.onInputKeyUp,
el: {
click: function (e) {
e.stopPropagation();
}
}
});
this.inputItem = Ext.create('Ext.form.field.Text', config);
this.menu.add(this.inputItem);
this.menu.showSeparator = false;
this.updateTask = Ext.create('Ext.util.DelayedTask', this.fireUpdate, this);
}
});
}
</script>
</head>
<body>
<form id="Form1" runat="server">
<ext:ResourceManager ID="ResourceManager1" runat="server" />
<ext:Viewport runat="server" Layout="FitLayout">
<Items>
<ext:GridPanel ID="GridPanel1" runat="server" Flex="1" SelectionMemory="false">
<Store>
<ext:Store ID="Store1" runat="server" RemoteSort="false" AutoLoad="true" PageSize="10">
<Model>
<ext:Model ID="Model1" runat="server" IDProperty="company">
<Fields>
<ext:ModelField Name="company" />
<ext:ModelField Name="industry" />
<ext:ModelField Name="price" Type="Float" />
<ext:ModelField Name="change" Type="Float" />
<ext:ModelField Name="pctChange" Type="Float" />
<ext:ModelField Name="lastChange" Type="Date" />
<ext:ModelField Name="visible" Type="Boolean" />
</Fields>
</ext:Model>
</Model>
</ext:Store>
</Store>
<ColumnModel ID="ColumnModel1" runat="server">
<Columns>
<ext:Column ID="Column1" runat="server" Text="Company" DataIndex="company" Hideable="true"
Width="200">
<Editor>
<ext:TextField ID="TextField1" runat="server" />
</Editor>
</ext:Column>
<ext:Column ID="Column2" runat="server" Text="Industry" DataIndex="industry" Hideable="true"
Width="200">
</ext:Column>
<ext:Column ID="Column3" runat="server" Text="Price" Width="75" DataIndex="price"
Hideable="false">
<Editor>
<ext:TextField ID="TextField2" runat="server" />
</Editor>
</ext:Column>
<ext:Column ID="Column4" runat="server" Text="Change" Width="100" DataIndex="change"
Hideable="false" />
<ext:Column ID="Column5" runat="server" Text="% Change" Width="100" DataIndex="pctChange"
Hideable="true" />
<ext:DateColumn ID="DateColumn1" runat="server" Text="Last Updated" Width="120" DataIndex="lastChange"
Hideable="true" Hidden="true" Format="MMM dd, yyyy" />
<ext:Column ID="Column6" runat="server" Text="Visible" DataIndex="visible" Align="Center"
Hideable="true">
<Renderer Handler="return (value) ? 'Yes':'No';" />
</ext:Column>
</Columns>
</ColumnModel>
<SelectionModel>
<ext:RowSelectionModel ID="RowSelectionModel1" runat="server" Mode="Single" />
</SelectionModel>
<Features>
<ext:GridFilters runat="server" Local="true">
<Filters>
<ext:StringFilter DataIndex="company" EmptyText="Type in description...">
</ext:StringFilter>
</Filters>
</ext:GridFilters>
</Features>
<BottomBar>
<ext:PagingToolbar ID="PagingToolbar1" runat="server">
<Items>
</Items>
</ext:PagingToolbar>
</BottomBar>
<View>
<ext:GridView ID="GridView1" runat="server">
</ext:GridView>
</View>
</ext:GridPanel>
</Items>
</ext:Viewport>
</form>
</body>
</html>