# ISysInfo.GetInfo()

Description:

The `GetInfo` method retrieves information about a system attribute.

This method can be called both synchronously and asynchronously.

Syntax:

For synchronous calls:

    result = so.ISysInfo.GetInfo(criteria);

For asynchronous calls:

    result = so.ISysInfo.GetInfo(criteria, callback);

Arguments:

- `criteria`:

  This is an object that specifies the system attribute about which to retrieve information. For more information about the object properties and how to define them, see section Criteria for retrieving system attribute information.

- `callback`:

  The `callback` argument is the name of the method that is executed when an asynchronous `GetInfo` call has results or status information to return. You must define this method separately. Follow the instructions in section Defining the callback handler for an asynchronous method to define the `callback` method.

  This argument is used only with an asynchronous `GetInfo` call.

Return value:

If synchronous, the `GetInfo` method returns an object that contains the requested system attribute information, an error code, and an error message.

Table: Return value properties for a synchronous GetInfo
Property | Description | Value
--- | --- | ---
`result.ReturnValue` | This is an object (a system attribute object) that contains the requested system attribute information. For example, if you request drive information using the `Memory - DriveInfo` system attribute, the `ReturnValue` object contains the properties `Entity` and `Key` as well as the properties for `DriveInfo`: `ReturnValue.Entity` `ReturnValue.Key` `ReturnValue.Drive` `ReturnValue.TotalSpace` `ReturnValue.FreeSpace` `ReturnValue.CriticalSpace` `ReturnValue.MediaType` `ReturnValue.BatteryState` `ReturnValue.DriveName` | See System attributes.
`result.ErrorCode` | This is a number that specifies a predefined error code. | See Service API error codes.
`result.ErrorMessage` | This is a text string that describes the error. | See SystemInfo Service API error messages.

If asynchronous, the `GetInfo` method returns an object that contains the initial return value for the asynchronous call it started (see the following table). The actual system attribute information is returned by the `callback` method in the `ReturnValue` property of its result object. The returned information (a system attribute object) is described in the preceding table.

Table: Return value properties for an asynchronous GetInfo
Property | Description | Value
--- | --- | ---
`result.TransactionID` | This is a number used as an identification to match transactions started with the asynchronous `GetInfo` call to one or more calls it generates to `callback`. |
`result.ErrorCode` | This is a number that specifies a predefined error code. | See Service API error codes.
`result.ErrorMessage` | This is a text string that describes the error. | See SystemInfo Service API error messages.

Example code:

For the complete source of a sample widget that demonstrates how to use this Service API, see the full example.