Layer.DisableOnError Property
Gets or sets a value specifying if an error within the layer should automatically disable the layer, or throw an exception.
Syntax
public System.Boolean DisableOnError { get; set; }Property Value
Default: false
A value specifying if an error within the layer should automatically disable the layer, or throw an exception.
Remarks
Normally when an error occurs in a layer during an update, an exception is thrown to the application from the View.Update method, or the MapControl.Error event is fired. Dealing with such errors is difficult if you want to do something a little better than just exiting the application.
Instead, if you set this property to True, the layer will catch the error internally, and automatically set the Enabled property to False. This will allow the application to continue executing, albeit with one map layer turned off. When this happens, the EnabledChanged event will also be fired. Using the event and the GetLastError method, the application can determine when a layer is automatically disabled because of an error, and act accordingly, perhaps by adding an error marker in a layer tree GUI control, and notifying the user.
The EnabledChanged event will typically be raised while there is ongoing map update, or on a background thread, for instance under a tile layer. In both these cases, the application should not try to deal with the error directly, but instead make sure the error handling code is invoked on the GUI thread, from the GUI event dispatcher.
If a layer is turned off due to an error, the application could try to re-enable the layer at a later time. In many cases this could work, if the underlying cause of error is corrected. In other cases, the same error might occur and the layer will immediately be turned off again. But it is also possible that doing this could make the application hang or crash.
So if you want to allow this, make sure to test your application in all error situations you can think of.
There are several other ways to handle certain types of errors in Carmenta Engine. For instance, all database and web based datasets and layers have events and methods that an application can use to reconnect to the service after a failure. All datasets also have the DataSet.SuppressInitializationErrors flag that can be used to ignore certain errors. See Dealing with errors for more information.
To use this functionality with the OgcWmsLayer and OgcWmtsLayer, you also need to set their HttpLayer.ThrowExceptions property to True.
Platforms
Windows, Linux, Android