Function DataChangeMonitorCreate(ID, monitoredIdentifiers[, excludeNonSaveables])


With the function DataChangeMonitorCreate, you can create a new data change monitor. With a data change monitor, you can determine whether any identifiers in a subset of AllIdentifiers have been changed since the latest call to DataChangeMonitorCreate or DataChangeMonitorReset. To check for any changes, you can use DataChangeMonitorHasChanged.

    ID,                     ! (input) a scalar string expression
    monitoredIdentifiers,   ! (input) subset of AllIdentifiers
    [excludeNonSaveables]   ! (optional) 0 or 1



A string identifying a (new) data change monitor.


The subset of identifiers that you want to monitor for this data change monitor.

excludeNonSaveables (optional)

If the data change monitor is used to monitor whether or not a subset of identifiers needs to be saved, it is unnecessary to include identifiers that have the Nosave property. If you set this argument to 1, these identifiers will automatically be excluded from the given subset of identifiers. The default of this argument is 1. This exclusion is applied also on any subset that is passed in later calls to DataChangeMonitorReset.

Return Value

The function returns 1 upon success. If there already exists a data change monitor for the given ID, the function returns 0. In case of any other error, it returns \(-1\). If the return value is 0 or \(-1\) CurrentErrorMessage will contain a proper error message.


  • The newly created monitor is reset automatically, so there is no need to call the function DataChangeMonitorReset immediately after creation.

  • If your project uses the Data management style ‘Disk files and folders’, AIMMS itself uses a data change monitor to keep track of whether the active data needs to be saved before exiting, or before loading any new data. The ID of this internal data change monitor is given by the predeclared string parameter DataManagementMonitorID.