Beispiel #1
0
        /// <summary>
        /// Performs a reverse <see cref="IExpressionNode.Resolve"/> operation, i.e. creates a <see cref="LambdaExpression"/> from a given resolved expression,
        /// substituting all <see cref="QuerySourceReferenceExpression"/> objects by getting the referenced objects from the lambda's input parameter.
        /// </summary>
        /// <param name="itemExpression">The item expression representing the items passed to the generated <see cref="LambdaExpression"/> via its input
        /// parameter.</param>
        /// <param name="resolvedExpression">The resolved expression for which to generate a reverse resolved <see cref="LambdaExpression"/>.</param>
        /// <returns>A <see cref="LambdaExpression"/> from the given resolved expression, substituting all <see cref="QuerySourceReferenceExpression"/>
        /// objects by getting the referenced objects from the lambda's input parameter. The generated <see cref="LambdaExpression"/> has exactly one
        /// parameter which is of the type defined by <paramref name="itemExpression"/>.</returns>
        public static LambdaExpression ReverseResolve(Expression itemExpression, Expression resolvedExpression)
        {
            ArgumentUtility.CheckNotNull("itemExpression", itemExpression);
            ArgumentUtility.CheckNotNull("resolvedExpression", resolvedExpression);

            var lambdaParameter = Expression.Parameter(itemExpression.Type, "input");
            var visitor         = new ReverseResolvingExpressionTreeVisitor(itemExpression, lambdaParameter);
            var result          = visitor.VisitExpression(resolvedExpression);

            return(Expression.Lambda(result, lambdaParameter));
        }
Beispiel #2
0
        /// <summary>
        /// Performs a reverse <see cref="IExpressionNode.Resolve"/> operation on a <see cref="LambdaExpression"/>, i.e. creates a new
        /// <see cref="LambdaExpression"/> with an additional parameter from a given resolved <see cref="LambdaExpression"/>,
        /// substituting all <see cref="QuerySourceReferenceExpression"/> objects by getting the referenced objects from the new input parameter.
        /// </summary>
        /// <param name="itemExpression">The item expression representing the items passed to the generated <see cref="LambdaExpression"/> via its new
        /// input parameter.</param>
        /// <param name="resolvedExpression">The resolved <see cref="LambdaExpression"/> for which to generate a reverse resolved <see cref="LambdaExpression"/>.</param>
        /// <param name="parameterInsertionPosition">The position at which to insert the new parameter.</param>
        /// <returns>A <see cref="LambdaExpression"/> similar to the given resolved expression, substituting all <see cref="QuerySourceReferenceExpression"/>
        /// objects by getting the referenced objects from an additional input parameter. The new input parameter is of the type defined by
        /// <paramref name="itemExpression"/>.</returns>
        public static LambdaExpression ReverseResolveLambda(Expression itemExpression, LambdaExpression resolvedExpression, int parameterInsertionPosition)
        {
            ArgumentUtility.CheckNotNull("itemExpression", itemExpression);
            ArgumentUtility.CheckNotNull("resolvedExpression", resolvedExpression);

            if (parameterInsertionPosition < 0 || parameterInsertionPosition > resolvedExpression.Parameters.Count)
            {
                throw new ArgumentOutOfRangeException("parameterInsertionPosition");
            }

            var lambdaParameter = Expression.Parameter(itemExpression.Type, "input");
            var visitor         = new ReverseResolvingExpressionTreeVisitor(itemExpression, lambdaParameter);
            var result          = visitor.VisitExpression(resolvedExpression.Body);

            var parameters = new List <ParameterExpression> (resolvedExpression.Parameters);

            parameters.Insert(parameterInsertionPosition, lambdaParameter);
            return(Expression.Lambda(result, parameters.ToArray()));
        }