beforerefresh

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The beforerefresh event may be called from web pages developed in Web Designer and processed by a USoft page engine service.

Event

Applies to

Occurs when

beforerefresh

Data source objects

Before a data source is refreshed

To refresh a data source programmatically, call its refresh() function.

How to use

Find or create an Event Listener object with Event Type = beforefresh. Event Listeners are in the Web Designer Controls catalog:

US_clip0009

Insert the event listener into the data source object. Insert a callClientScript action into the event listener. Use this action's Script property to code the behaviour that you want to see when the event occurs. A typical pattern is to specify the condition under which you want processing to be blocked, to block the process, and to give an error message in an alert box. This pattern looks like this:

if ( condition-not-satisfied ) {

  options.success = false;

  alert( message );

}

You are implicitly associating the event with an event handler function. This function has an options parameter. For available options, see the Options section at the end of this help topic:

function(evtoptions){ ... }

Or you can create the event handler more explicitly by calling $.udb('data-source').on().

Options

When the event occurs, the following event handler function is called. You can use this function's options parameter in your event scripting.

function( 'beforerefresh'options ){}

 

options   ::=  event-options

 

event-options   ::=  {

     success:  success,

     options:  caller-options

}

 

success  ::=  { true | false }

This syntax means that you can access the success option by scripting: options.success, and that you can access the caller options by scripting options.options.caller-option.

If you set success to false, processing is interrupted. As a result, refresh will not take place.

Caller-options are the options exposed by the .refresh() function of the calling data source object.