Class RelayCommand<T>

Implementation of IRelayCommand that allows for CommandParameter to be passed in.

Inheritance
object
RelayCommand<T>
Implements
Inherited Members
Namespace: Unity.AppUI.MVVM
Assembly: Unity.AppUI.MVVM.dll
Syntax
public class RelayCommand<T> : IRelayCommand<T>, IRelayCommand, ICommand
Type Parameters
Name Description
T

The type of the CommandParameter.

Constructors

RelayCommand(Action<T?>)

Initializes a new instance of the RelayCommand<T> class.

Declaration
public RelayCommand(Action<T?> execute)
Parameters
Type Name Description
Action<T> execute

The action to execute.
Exceptions
Type Condition
ArgumentNullException

Thrown if the action is null.

RelayCommand(Action<T?>, Predicate<T?>)

Initializes a new instance of the RelayCommand<T> class.

Declaration
public RelayCommand(Action<T?> execute, Predicate<T?> canExecute)
Parameters
Type Name Description
Action<T> execute

The action to execute.
Predicate<T> canExecute

The predicate executed to determine if the command can execute.
Exceptions
Type Condition
ArgumentNullException

Thrown if the action or the predicate is null.

Methods

CanExecute(object?)

Determines whether this RelayCommand<T> can execute in its current state.

Declaration
public bool CanExecute(object? parameter)
Parameters
Type Name Description
object parameter

Data used by the command.
Returns
Type Description
bool

true if this command can be executed; otherwise, false.
Exceptions
Type Condition
InvalidOperationException

Thrown if the parameter is not of type T.

CanExecute(T?)

Determines whether this RelayCommand<T> can execute in its current state.

Declaration
public bool CanExecute(T? parameter)
Parameters
Type Name Description
T parameter

Data used by the command.
Returns
Type Description
bool

true if this command can be executed; otherwise, false.

Execute(object?)

Executes the RelayCommand<T> on the current command target.

Declaration
public void Execute(object? parameter)
Parameters
Type Name Description
object parameter

Data used by the command.
Exceptions
Type Condition
InvalidOperationException

Thrown if the parameter is not of type T.

Execute(T?)

Executes the RelayCommand<T> on the current command target.

Declaration
public void Execute(T? parameter)
Parameters
Type Name Description
T parameter

Data used by the command.

NotifyCanExecuteChanged()

Notifies that the CanExecuteChanged property has changed.

Declaration
public void NotifyCanExecuteChanged()

Events

CanExecuteChanged

Event raised when CanExecute(object?) changes.

Declaration
public event EventHandler? CanExecuteChanged
Event Type
Type Description
EventHandler

Implements