/// <summary>
/// Combine property selector expression with predicate,
/// passing property from selector expression as parameter.
/// </summary>
/// <param name="propertySelector">property selector expression.</param>
/// <param name="propertyPredicate">predicate expression taking property as parameter. </param>
/// <typeparam name="T1">type of property selector source. </typeparam>
/// <typeparam name="T2">type of predicate parameter. </typeparam>
/// <returns>combined predicate expression with property as parameter. </returns>
public static Expression <Func <T1, bool> > Compose <T1, T2>(
this Expression <Func <T1, T2> > propertySelector,
Expression <Func <T2, bool> > propertyPredicate)
{
return(ParameterToMemberExpressionRebinder.CombinePropertySelectorWithPredicate(
propertySelector,
propertyPredicate));
}
/// <summary>
/// Pass property selector expression as parameter to lambda expression with single parameter of selected property type.
/// </summary>
/// <param name="propertySelector">Property selector lambda expression.</param>
/// <param name="lambdaExpression">Lambda expression taking given property as parameter. </param>
/// <typeparam name="TSource">>Type of source object from where property is selected.</typeparam>
/// <typeparam name="TNavigate">Type of property returned by property selector and used by lambda expression. </typeparam>
/// <typeparam name="TResult">Type of return value for lambda expression. </typeparam>
/// <returns>Lambda expression with given property as parameter.</returns>
public static Expression <Func <TSource, TResult> > NavigatePropertySelectorsToNextLambda <TSource, TNavigate, TResult>(
Expression <Func <TSource, TNavigate> > propertySelector, Expression <Func <TNavigate, TResult> > lambdaExpression)
{
var memberExpression = propertySelector.Body as MemberExpression;
if (memberExpression == null)
{
throw new ArgumentException("propertySelector");
}
var expr = Expression.Lambda <Func <TSource, TResult> >(lambdaExpression.Body, propertySelector.Parameters);
var rebinder = new ParameterToMemberExpressionRebinder(lambdaExpression.Parameters[0], memberExpression);
expr = (Expression <Func <TSource, TResult> >)rebinder.Visit(expr);
return(expr);
}
/// <summary>
/// Combine property selector expression with lambda expression function,
/// passing property from selector expression as parameter.
/// </summary>
/// <param name="propertySelector">property selector expression.</param>
/// <param name="lambdaExpression">lambda expression taking property as parameter. </param>
/// <typeparam name="TSource">type of property selector source. </typeparam>
/// <typeparam name="TNavigate">type of property and lambda expression parameter. </typeparam>
/// <typeparam name="TResult">type lambda expression return value. </typeparam>
/// <returns>combined lambda expression with property as parameter. </returns>
public static Expression <Func <TSource, TResult> > Navigate <TSource, TNavigate, TResult>(
this Expression <Func <TSource, TNavigate> > propertySelector, Expression <Func <TNavigate, TResult> > lambdaExpression)
{
return(ParameterToMemberExpressionRebinder.NavigatePropertySelectorsToNextLambda(propertySelector, lambdaExpression));
}
