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GridColumn.Validate Event

wpf-devexpress-dot-xpf-dot-grid-dot-gridcolumn.md

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GridColumn.Validate Event

Allows you to validate the focused cell’s data in the current column.

Namespace : DevExpress.Xpf.Grid

Assembly : DevExpress.Xpf.Grid.v25.2.dll

NuGet Package : DevExpress.Wpf.Grid.Core

Declaration

csharp
public event GridCellValidationEventHandler Validate
vb
Public Event Validate As GridCellValidationEventHandler

Event Data

The Validate event's data class is GridCellValidationEventArgs. The following properties provide information specific to this event:

PropertyDescription
CancellationTokenGets an object that notifies that the Update operation should be canceled. Inherited from GridRowValidationEventArgs.
CellGets a processed cell.
CellValueGets the cell’s old valid value.
ColumnGets the column that contains the processed cell.
CultureGets the culture related to the validation. Inherited from ValidationEventArgs.
ErrorContentGets or sets an object that describes the validation error. Inherited from ValidationEventArgs.
ErrorTypeGets or sets the error icon type. Inherited from ValidationEventArgs.
HandledGets or sets a value that indicates the present state of the event handling for a routed event as it travels the route. Inherited from RoutedEventArgs.
IsNewItemInherited from GridRowValidationEventArgs.
IsValidGets or sets a value specifying whether the value is valid. Inherited from ValidationEventArgs.
OriginalSourceGets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class. Inherited from RoutedEventArgs.
RoutedEventGets or sets the RoutedEvent associated with this RoutedEventArgs instance. Inherited from RoutedEventArgs.
RowGets the processed row. Inherited from GridRowValidationEventArgs.
RowHandleGets the processed row’s handle. Inherited from GridRowValidationEventArgs.
SourceGets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs.
UpdateRowResultGets or sets a task that allows you to asynchronously post changes to an underlying data source (database). Inherited from GridRowValidationEventArgs.
UpdateSourceGets the action that caused the validation. Inherited from ValidationEventArgs.
UseCancellationTokenGets or sets whether the Update operation can be canceled. Inherited from GridRowValidationEventArgs.
ValueGets the editor’s value. Inherited from ValidationEventArgs.

The event data class exposes the following methods:

MethodDescription
InvokeEventHandler(Delegate, Object)When overridden in a derived class, provides a way to invoke event handlers in a type-specific way, which can increase efficiency over the base implementation. Inherited from RoutedEventArgs.
OnSetSource(Object)When overridden in a derived class, provides a notification callback entry point whenever the value of the Source property of an instance changes. Inherited from RoutedEventArgs.
SetError(Object, ErrorType)Marks the processed input value as invalid and displays an error within the editor with the specified error icon type. Inherited from ValidationEventArgs.
SetError(Object)Marks the processed input value as invalid and displays an error within the editor. Inherited from ValidationEventArgs.

Remarks

When a user modifies the focused cell’s value and tries to save the changes (by pressing the ENTER key or moving focus to another cell), the grid validates a new value. First, this value is validated by the editor itself. Then, the column’s Validate event is raised, allowing you to manually validate the cell’s value. Note this event is not fired when changing cell values in code.

Note

When you use a custom CellTemplate, input validation is supported only if the template contains a BaseEdit class descendant declared as demonstrated in the following topic: Custom In-Place Cell Editors.

Refer to the following help topic for more information: Cell Validation.

See Also

Row Validation

Interface-Based Validation

GridColumn Class

GridColumn Members

DevExpress.Xpf.Grid Namespace