CallbackEventArgsBase.Parameter Property
Gets a string that contains specific information (if any) passed from the client side.
Namespace: DevExpress.Web
Assembly: DevExpress.Web.v22.2.dll
NuGet Package: DevExpress.Web
Declaration
Property Value
| Type | Description |
|---|---|
| String | A string value that contains specific information collected on the client side and passed to the event for further server-side processing. |
Remarks
Use the Parameter property to obtain specific information which has been collected on the client side and passed via a web control’s PerfromCallback (or SendCallback) method to the server for further server-side processing.
Example
The example below demonstrates how to manipulate ASPxHtmlEditor View Areas by CustomToolbarButton.
- Wrap the ASPxHtmlEditor with the ASPxCallbackPanel to programmatically send a callback to the server.
- Define custom toolbar buttons (CustomToolbarButton) for the ASPxHtmlEditor.
- Handle the client-side ASPxClientHtmlEditor.CustomCommand event and perform a callback by using the ASPxClientCallbackPanel.PerformCallback method.
- Handle the ASPxCallbackPanel.Callback event and define View Areas enabled by the ASPxHtmlEditor.Settings property.
<script type="text/javascript">
function OnCustomCommand(s, e) {
if(e.commandName == "close") {
cp.PerformCallback("closed");
}
if(e.commandName == "open" || e.commandName == "new")
if(confirm("Are you sure?"))
cp.PerformCallback("opened");
}
</script>
</head>
<body>
<form id="form1" runat="server">
<dx:ASPxCallbackPanel ID="cp" runat="server" ClientInstanceName="cp" OnCallback="cp_Callback">
<PanelCollection>
<dx:PanelContent ID="PanelContent1" runat="server" SupportsDisabledAttribute="True">
<dx:ASPxHtmlEditor ID="htmlEditor" runat="server">
<ClientSideEvents CustomCommand="OnCustomCommand" />
<Toolbars>
<dx:HtmlEditorToolbar>
<Items>
<dx:CustomToolbarButton CommandName="new" Text="New">
</dx:CustomToolbarButton>
<dx:CustomToolbarButton CommandName="open" Text="Open">
</dx:CustomToolbarButton>
<dx:CustomToolbarButton CommandName="save" Text="Save">
</dx:CustomToolbarButton>
<dx:CustomToolbarButton CommandName="close" Text="Close">
</dx:CustomToolbarButton>
</Items>
</dx:HtmlEditorToolbar>
</Toolbars>
</dx:ASPxHtmlEditor>
</dx:PanelContent>
</PanelCollection>
</dx:ASPxCallbackPanel>
</form>
</body>
</html>
using System;
public partial class _Default : System.Web.UI.Page {
protected void Page_Load(object sender, EventArgs e) {
if(!IsPostBack && !IsCallback)
Session["ViewVisible"] = false;
if(Session["ViewVisible"]!=null) {
htmlEditor.Settings.AllowHtmlView = (bool)Session["ViewVisible"];
htmlEditor.Settings.AllowPreview = (bool)Session["ViewVisible"];
}
}
protected void cp_Callback(object sender, DevExpress.Web.ASPxClasses.CallbackEventArgsBase e) {
if(e.Parameter == "opened") {
htmlEditor.Settings.AllowHtmlView = true;
htmlEditor.Settings.AllowPreview = true;
Session["ViewVisible"] = true;
}
if(e.Parameter == "closed") {
htmlEditor.Settings.AllowHtmlView = false;
htmlEditor.Settings.AllowPreview = false;
Session["ViewVisible"] = false;
}
}
}
See Also