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Modifying Web.config

It is recommended that you add EO.Web.Runtime into your web.config's httpModules list in order to properly handle server side redirection. Without properly configuring EO.Web httpModule, EO.Web Callback/CallbackPanel will function but will not be able to properly handle server side redirection, such as an automatic redirection to login page when user session times out.

Trigger Callback request

Not a single line of JavaScript is needed.

Simply set Callback or CallbackPanel's Triggers property to specify a list of the controls that could be used to trigger Callback. When one of the triggering controls sends postback request to server, this postback request will be automatically handled by the Callback or CallbackPanel control's Execute event handler.

If you do not want to use Triggers for any reasons, then you will need to manually trigger Callback. See the following topic for details.

Client-side JavaScript to trigger Callback

Call global function eo_Callback to trigger a callback.

eo_Callback('Callback1', inputParam);                

The first parameter 'Callback1' is the client ID of the Callback control. The second parameter is the input parameter that will be passed to server side Execute event handler.

Server-side Callback's Execute event handler

When the call back process is triggered, server-side event handler will be called to execute the backend logic and return the result.

[C#]
private void Callback1_Execute(object sender, EO.Web.CallbackEventArgs e)
{    
}

Important Properties

The following table lists all the important Callback properties: