Handle and extract data from Callbacks

Declare and initialize the variables in your cash register application, and pass them as arguments with the COM extension methods.

The COM extension assigns values to these variables. The cash register can use these variables to access, store, and process the data returned from the library through the COM.

The additional data construct provides this data in the responseHeader. We provide a helper method to aid processing this in your cash register application

Variable

Name	Description
Any, for example: `intCallResult`	Variable used to demonstrate passing variables as arguments.

Method

Name	Description
`GetTenderState`	Use this method to access the relevant tender state in the same header.

This mechanism applies to progress events, Additional data callback, Handle the Dynamic Currency Conversion (DCC) callback, Print Receipt callback, and the Final State callback.

Code example

[Some Callback Event](objPED, objTender, objHeader)
Dim additionalDataKey, additionalDataValue
For i=1 To objHeader.GetAdditionalData().Count
    intCallResult = objHeader.GetAdditionalData().GetData(i,
    additionalDataKey, additionalDataValue)
'Add results to internal array for later processing
'...
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