Hi zikr,
You can't cancel event. But you can set oldValue back if validation fail
Please see example
<%@ Page Language="C#" EnableViewState="false" %>
<%@ Import Namespace="System.Globalization"%>
<%@ Register Assembly="Coolite.Ext.Web" Namespace="Coolite.Ext.Web" TagPrefix="ext" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>Example</title>
<script runat="server">
protected void WorkingDate_Change(object sender, AjaxEventArgs e)
{
CultureInfo provider = CultureInfo.InvariantCulture;
DateTime oldValue = DateTime.MinValue;
DateTime newValue = DateTime.MinValue;
if (!string.IsNullOrEmpty(e.ExtraParams["oldValue"]))
{
oldValue = DateTime.ParseExact(e.ExtraParams["oldValue"], "dd/MM/yyyy", provider);
}
if (!string.IsNullOrEmpty(e.ExtraParams["newValue"]))
{
newValue = DateTime.ParseExact(e.ExtraParams["newValue"], "dd/MM/yyyy", provider);
}
//some validation and if fail then revert value
if(oldValue != DateTime.MinValue)
{
DateField df = sender as DateField;
df.SetValue(oldValue);
df.AddScript("alert('{0}');", "The value change has been canceled");
}
}
</script>
</head>
<body style="padding:10px;">
<form id="form1" runat="server">
<ext:ScriptManager ID="ScriptManager1" runat="server" ScriptMode="Debug" />
<ext:DateField ID="WorkingDate" runat="server" Format="D" Width="180" ReadOnly="true"
StartDay="1">
<AjaxEvents>
<Change OnEvent="WorkingDate_Change">
<ExtraParams>
<ext:Parameter Name="newValue" Value="newValue.format ? newValue.format('d/m/Y') : ''" Mode="Raw" />
<ext:Parameter Name="oldValue" Value="oldValue.format ? oldValue.format('d/m/Y') : ''" Mode="Raw" />
</ExtraParams>
</Change>
</AjaxEvents>
</ext:DateField>
</form>
</body>
</html>
