public static PredicateAndHandler CreateFunc(object func, bool handlerFirstArgumentShouldBeBaseType=false)
{
var funcHandler = new PredicateAndHandler(HandlerKind.Func, handlerFirstArgumentShouldBeBaseType);
funcHandler.Arguments = new[] { new Argument(funcHandler, func, true) };
return funcHandler;
}
public static PredicateAndHandler CreateAction(object action, object predicate = null, bool handlerFirstArgumentShouldBeBaseType=false)
{
if(predicate == null)
{
var actionHandler = new PredicateAndHandler(HandlerKind.Action, handlerFirstArgumentShouldBeBaseType);
actionHandler.Arguments = new[] { new Argument(actionHandler, action, true) };
return actionHandler;
}
var predicateActionHandler = new PredicateAndHandler(HandlerKind.ActionWithPredicate, handlerFirstArgumentShouldBeBaseType);
predicateActionHandler.Arguments = new[] { new Argument(predicateActionHandler, action, true), new Argument(predicateActionHandler, predicate, false) };
return predicateActionHandler;
}
private static void AddActionHandlerWithPredicateExpressions(PredicateAndHandler handler, List <Expression> body, Expression argumentExpression, LabelTarget returnTarget)
{
//Add this code to the body:
// if(predicate(arg))
// {
// action(arg);
// return true;
// }
body.Add(
Expression.IfThen(
Expression.Invoke(handler.PredicateExpression, argumentExpression),
Expression.Block(
Expression.Invoke(handler.ActionOrFuncExpression, argumentExpression),
Expression.Return(returnTarget, Expression.Constant(true))
)));
}
/// <summary>
/// Adds a handler that is called if the item being matched is of type <paramref name="handlesType"/>.
/// The handler should return <c>true</c> if the item sent in matched and was handled.
/// <remarks>Note that if a previous added handler handled the item, this <paramref name="handler"/> will not be invoked.</remarks>
/// </summary>
/// <param name="handlesType">The type that it must match in order for <paramref name="handler"/> to be called.</param>
/// <param name="handler">The handler that is invoked. It should return <c>true</c> if the item sent in matched and was handled.</param>
/// <exception cref="ArgumentException">
/// This exception is thrown if the given <paramref name="handler"/> cannot handle the given <paramref name="handlesType"/>.
/// </exception>
/// <exception cref="ArgumentOutOfRangeException">
/// This exception is thrown if the current state is unknown.
/// </exception>
/// <exception cref="InvalidOperationException">
/// This exception is thrown if a handler that catches all messages has been added or a partial action has already been built.
/// </exception>
public void Match(Type handlesType, Func <TItem, bool> handler)
{
EnsureCanAdd();
EnsureCanHandleType(handlesType);
AddHandler(handlesType, PredicateAndHandler.CreateFunc(handler, true));
}
