public static IQueryable Join(this IQueryable outer, IQueryable inner, Func <ParameterExpression, Expression> outerKeySelector, Func <ParameterExpression, Expression> innerKeySelector, Func <ParameterExpression, ParameterExpression, Expression> resultSelector = null)
{
var touter = outer.ElementType;
var tinner = inner.ElementType;
return(outer.Join(inner, ExpressionEx.Func(touter.AsParameter(), outerKeySelector), ExpressionEx.Func(tinner.AsParameter(), innerKeySelector), resultSelector));
}
public static MethodCallExpression Select(this Expression source, Func <ParameterExpression, Expression> selector)
{
var itemType = source.Type.GetEnumerableItemType();
var selectorExpr = ExpressionEx.Func(itemType.AsParameter(), selector);
var res = source.CallEnumerable("Select", new[] { itemType, selectorExpr.ReturnType }, selectorExpr);
return(res);
}
public static IQueryable GroupJoin(this IQueryable outer, IQueryable inner, Func <ParameterExpression, Expression> outerKeySelector, Func <ParameterExpression, Expression> innerKeySelector, Func <ParameterExpression, ParameterExpression, Expression> resultSelector)
{
var touter = outer.ElementType;
var tinner = inner.ElementType;
var outerKeySelectorExpr = ExpressionEx.Func(touter.AsParameter(), outerKeySelector);
var innerKeySelectorExpr = ExpressionEx.Func(tinner.AsParameter(), innerKeySelector);
var resultSelectorExpr = ExpressionEx.Func(touter.AsParameter(), tinner.AsEnumerableType().AsParameter(), resultSelector);
var tkey = outerKeySelectorExpr.ReturnType;
return(outer.Transform(outer.CallQueryable("GroupJoin", new Type[] { touter, tinner, tkey, resultSelectorExpr.ReturnType }, inner.Expression, outerKeySelectorExpr.Quote(), innerKeySelectorExpr.Quote(), resultSelectorExpr.Quote())));
}
public static IQueryable GroupJoin(this IQueryable outer, IQueryable inner, LambdaExpression outerKeySelector, LambdaExpression innerKeySelector)
{
var touter = outer.ElementType;
var tinner = inner.ElementType;
var tkey = outerKeySelector.ReturnType;
var resultSelectorExpression = ExpressionEx.Func(
touter.AsParameter(),
typeof(IEnumerable <>).MakeGenericType(tinner).AsParameter(),
(element, joinedElements) => GenericGroupJoinItem.CreateNewExpression(element, joinedElements)
);
return(outer.Transform(outer.CallQueryable("GroupJoin", new Type[] { touter, tinner, tkey, resultSelectorExpression.ReturnType }, inner.Expression, outerKeySelector.Quote(), innerKeySelector.Quote(), resultSelectorExpression.Quote())));
}
//public static MethodCallExpression Call(this LambdaExpression func, params Expression[] arguments)
//{
// return Expression.Call(
// typeof(LinqExt.Linq.Extensions),
// "Invoke",
// func.Type.GetGenericArguments(),
// new[] { func }.Concat(arguments.EmptyIfNull()).ToArray()
// );
//}
public static MethodCallExpression OrderBy(this Expression source, Func <ParameterExpression, Expression> keySelector, bool firstKey = true, bool descending = false)
{
var methodName = firstKey ? "OrderBy" : "ThenBy";
if (descending)
{
methodName += "Descending";
}
var itemType = source.Type.GetEnumerableItemType();
var keySelectorExpr = ExpressionEx.Func(itemType.AsParameter(), keySelector);
var res = source.CallEnumerable(methodName, new[] { itemType, keySelectorExpr.ReturnType }, keySelectorExpr);
return(res);
}
public static IQueryable Join(this IQueryable outer, IQueryable inner, LambdaExpression outerKeySelectorExpr, LambdaExpression innerKeySelectorExpr, Func <ParameterExpression, ParameterExpression, Expression> resultSelector = null)
{
var touter = outer.ElementType;
var tinner = inner.ElementType;
var tkey = outerKeySelectorExpr.ReturnType;
if (resultSelector == null)
{
resultSelector = (left, right) => GenericJoinItem.CreateNewExpression(left, right);
}
var resultSelectorExpr = ExpressionEx.Func(touter.AsParameter(), tinner.AsParameter(), resultSelector);
return(outer.Transform(outer.CallQueryable("Join", new Type[] { touter, tinner, tkey, resultSelectorExpr.ReturnType }, inner.Expression, outerKeySelectorExpr.Quote(), innerKeySelectorExpr.Quote(), resultSelectorExpr.Quote())));
}