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Validating Nodes and Node Cells

The TreeList View provides two event handlers allowing you to manually validate entire nodes as individual data cells. These events are:

Event Description
TreeListView.ValidateNode This event is automatically fired when a node is about to lose focus, allowing you to specify whether the focused node's data is valid and whether the node can lose focus.
TreeListView.ValidateCell Occurs before the focused cell's modified value is posted to a data source, allowing you to manually validate its new value and specify whether or not the cell's editor can be closed.

These validation events provide properties allowing you to identify the processed node or cell, specify error type and content. To specify whether a node or cell contains invalid data, set the event parameter's IsValid property to false.

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