Creates a List from an IEnumerable. Computes the sum of the sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence. I chained them four (2outsidex2inside) times just to show that the type information is not lost in subsequent calls. LINQ) once? Invokes a transform function on each element of a sequence and returns the maximum nullable Single value. IMO the performance cost(brought by boxing) is unavoidable if you want a collection of objects with a collection of value-types given. The start time is equivalent to 19:00 (7PM) in Central Hi all) \$\begingroup\$ @mecab95 Make an interface out of the object type and have that be the list type. C# - Cast object to IEnumerable - iTecNote Do not be mistaken - IEnumerable doesn't implement IEnumerable - the only reason you can cast IEnumerable to IEnumerable is that IEnumerable is co-variant. Installation & Configuration. On the other hand, if you still want to use IEnumerable, use List, store your object in it, and then do the LINQ query! Enumerable.Cast extension method fails to cast from int to long, why? Returns a specified number of contiguous elements from the start of a sequence. Is it okay to return IEnumerable<KeyValuePair<string, string>> from a private method instead of returning a read-only dictionary? Returns the only element of a sequence, or a default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence. Returns the element at a specified index in a sequence or a default value if the index is out of range. #. Creates a Dictionary from an IEnumerable according to a specified key selector function, a comparer, and an element selector function. The returned IEnumerator provides the ability to iterate through the collection by exposing a Current property. Everything works except that I get the error: Groups the elements of a sequence according to a specified key selector function. Sorts the elements of a sequence in ascending order by using a specified comparer. publicinterfaceDBActive{voidWriteToDB();}, //Encapsulateyour'GetPropertyByName'methodasafunctionofyourclass. Some information relates to prerelease product that may be substantially modified before its released. Produces a sequence of tuples with elements from the two specified sequences. Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. value type. [Solved]-Cast from IEnumerable to IEnumerable<object>-LINQ,C# #, Dec 12 '08
Func, Func, IEqualityComparer, Enumerates and transforms a sequence, and produces an immutable sorted dictionary of its contents by using the specified key comparer. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use. Despite I really do not like this approach, I know it is possible to provide a toolset similar to LINQ-to-Objects that is callable directly on an IEnumerable interface, without forcing a cast to IEnumerable (bad: possible boxing!) Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements. Returns a DataTable that contains copies of the DataRow objects, given an input IEnumerable object where the generic parameter T is DataRow. Converts an IEnumerable to an IQueryable. We and our partners use cookies to Store and/or access information on a device. Projects each element of a sequence to an IEnumerable, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein. c# - Dynamically casting to IEnumerable<T> or T - Stack Overflow The OP didn't ask if it made sense, just how to do it. The elements of each group are projected by using a specified function. [Solved] Cast object to IEnumerable | 9to5Answer Returns the last element of a sequence that satisfies a condition or a default value if no such element is found. Creates a Dictionary from an IEnumerable according to specified key selector and element selector functions. If the object you receive is not an enumerable or a derivate it won't work. without the need to differentiate between DirectCast/CType. Produces the set intersection of two sequences by using the specified IEqualityComparer to compare values. Func, Func, Func, To subscribe to this RSS feed, copy and paste this URL into your RSS reader. Returns a new enumerable collection that contains the last count elements from source. You have to create a List first and add your object to that list, as, List<MyClass.Inventory> lst = new List<MyClass.Inventory> (); lst.Add (inventory); Not sure why do you need this, but once i saw next extension method: public static class CustomExtensions { public static IEnumerable<T> ToEnumerable<T> (this T input) { yield return . The keys are compared by using a comparer and each group's elements are projected by using a specified function. Do not be mistaken - IEnumerable<string> doesn't implement IEnumerable<object> - the only reason you can cast IEnumerable<string> to IEnumerable<object> is that IEnumerable<T> is co-variant. There are two reasons why this will normally work for most types that are considered "sequences". I have a tabbed form. The following example demonstrates how to implement the IEnumerable<T>interface and how to use that implementation to create a LINQ query. I am assuming Hi, System.Reflection.PropertyInfomyProperty=this.GetType().GetProperty(p_propertyName); objectres=myProperty.GetValue(this,null); System.Reflection.MethodInfomi=t.GetMethod("ToArrayList"). Cast collection from IGrouping to IEnumerable, c# Linq or code to extract groups from a single list of source data, Convert / Cast IEnumerable to IEnumerable, The specified cast from a materialized 'System.Int32' type to the 'System.Double' type is not valid. And if I go back and decide to change the type of the Customer.Orders down the track (say from ObservableCollection to IList) then I need to change that declaration too - something I wouldn't have to do if I'd used var in the first place. By clicking Post Your Answer, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct. If MyClass<T> is initialized as for example MyClass<List<string>> then T = List<string> so the overloaded definition won't actually get invoked. :-). ",s);}, publicFunplace(stringname){this.s=name;}, publicstringName{get{returnthis.s;}}, publicvoidWriteToDB(){Console.WriteLine("WroteFunplace{0}toDB. Mapping to Enumerable.Empty<T> throws in netcoreapp3.1 #3365 - GitHub I want to limit the amount of data shown in a page coming from a database. If there is not any related data objects the database mapper assigns the related data property Enumerable.Empty<T>. The point was to show that the 'entry point' takes a nongeneric IEnumerable and that is resolved wherever it can be. However, I also prefer to use IEnumerable, f. Is 'selectedDataItem' a array or single Object ? Produces the set difference of two sequences according to a specified key selector function. Returns the maximum value in a generic sequence according to a specified key selector function. IEqualityComparer), ToImmutableHashSet(IEnumerable), ToImmutableHashSet(IEnumerable, IEqualityComparer), ToImmutableList(IEnumerable), ToImmutableSortedDictionary(IEnumerable, Func, Func), ToImmutableSortedDictionary(IEnumerable, Func, Func, IComparer), ToImmutableSortedDictionary(IEnumerable, Select from IEnumerable with Distinct/GroupBy and sorting possible? @Aniket - There is quite definitely a point. Not the answer you're looking for? You can easily adapt the code to make it a normal LINQ-to-Objects .Count() method. Cast object to IEnumerable c# casting ienumerable 30,713 Solution 1 Just do this: var enumerable = new [] { inventory }; Solution 2 Not sure why do you need this, but once i saw next extension method: public static class CustomExtensions { public static IEnumerable<T> ToEnumerable<T> (this T input) { yield return input; } } Solution 3 Dec 11 '08
Projects each element of a sequence to an IEnumerable and flattens the resulting sequences into one sequence. Some of our partners may process your data as a part of their legitimate business interest without asking for consent. Enumerable.Cast<TResult> and Enumerable.OfType<TResult> methods are real life savers in those kind of situations. "Unable to cast object of type Hi, Using LINQ expression to retrieve IEnumerable of properties from IEnumerable of POCO, Passing Func to Where changes return type from IQueryable to IEnumerable, How to pass LinQ Expressions from F# to C# code. Correlates the elements of two sequences based on matching keys. Find centralized, trusted content and collaborate around the technologies you use most. Countering the Forcecage spell with reactions? Please change IQuerable<string> to IEnumerable<string> instead. I'm using NHibernate 1.2 (CR1), and I'm using a custom list (inherited from The actual problem is in GetUserDetailsIsActiveMenuAndOnSchedule, not this code.You can use a record to define the result type you want in a single line, eg public . Determines whether a sequence contains any elements. The generic IEnumerable<T> interface inherits from IEnumerable, so the cast should work fine for the generic collection classes in System.Collections.Generic, LINQ sequences etc. Projects each element of a sequence into a new form. I have come to the part with public Customers(). BindingList(Of T) ) for all my lists. Creates a HashSet from an IEnumerable using the comparer to compare keys. Converts a generic IEnumerable to a generic IQueryable. When you implement IEnumerable<T>, you must also implement IEnumerator<T>or, for C# only, you can use the yieldkeyword. If it is a plain IEnumerable then you'll need to create another method that converts it to the correct IEnumerable<T> type, as in the following solution: IEnumerable<T> Convert<T> (IEnumerable source, T firstItem) { // Note: firstItem parameter is unused and is just for resolving type of T foreach (var item in source) { yield return (T)item . Invokes a transform function on each element of a sequence and returns the minimum Single value. Map IEnumerable<dynamic> list to another object - Stack Overflow Enumerates and transforms a sequence, and produces an immutable sorted dictionary of its contents. Computes the average of a sequence of nullable Int32 values that are obtained by invoking a transform function on each element of the input sequence. Computes the average of a sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence. Attempts to determine the number of elements in a sequence without forcing an enumeration. Manage Settings I used Hi all, Map a Complex Object to a List of Objects using AutoMapper I am following this code Returns the maximum value in a generic sequence. Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support. Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence. Returns a specified range of contiguous elements from a sequence. #. Invokes a transform function on each element of a generic sequence and returns the minimum resulting value. Invokes a transform function on each element of a sequence and returns the minimum nullable Decimal value. I have code that looks like this: Sorts the elements of a sequence in descending order by using a specified comparer. Key values are compared by using a specified comparer, and the elements of each group are projected by using a specified function. All rights reserved. IEnumerable<T> Interface (System.Collections.Generic) *accessed* such that I may build a least-recently-used cache that I have the following example classes: Hi All, Invokes a transform function on each element of a sequence and returns the maximum nullable Double value. How can I cast IEnumerable<?> to IEnumerable<string>? Creates a HashSet from an IEnumerable. Enumerates a sequence, produces an immutable sorted set of its contents, and uses the specified comparer. Is 'selectedDataItem' a array or single Object ? Sorts the elements of a sequence in ascending order. I have a class that defines one, ",s);}, publicclassWorkplaces:NewPluralEntity{}, publicclassFunplaces:NewPluralEntity{}, //TheclasscontainingyourcollectionofWorkplaces, publicInsured(){this.internalList=newWorkplaces();}, publicWorkplacesPlacesToWork{get{returnthis.internalList;}}, publicoverrideNewPluralEntityGetListOfPlaces(){. Methinks not*, The next Access Europe meeting is on Wed 7 June - Northwind 2.0 Developer Edition Inventory and String functions, Adding up only highest 7 numbers in a table, How to deploy AntDB Community Version on a virtual machine on VMware WorkstationP2, How to deploy AntDB Community Version on a virtual machine on VMware WorkstationP3, The next Access Europe meeting is on Wed 5 July - Interactive Gantt Chart Scheduler in Access, publicabstractclassNewPluralEntity:ICollection,IEnumerable, publicclassWorkplaces:NewPluralEntity, publicArrayListGetNewPluralEntityPropertyUsingReflection(stringp_propertyName). Correlates the elements of two sequences based on equality of keys and groups the results. Constructs an immutable dictionary based on some transformation of a sequence. Nevertheless, it seems that you can get something-like-linq working "directly" on things hidden behind nongeneric IEnumerable. Although VMessage may contain the same members as Message, they are different and unrelated types, so you cannot cast from one to the other in C#.. What you need to do is convert each VMessage to a Message.. One way is to use LINQ: var convertMessages = listMessages.Select(x => new Message { IdTicket = x.IdTicket, IdMessage = x.IdMessage, Text = x.Text, }); var TData = new TicketData . What are the advantages and disadvantages of the callee versus caller clearing the stack after a call? Enumerates and transforms a sequence, and produces an immutable dictionary of its contents by using the specified key comparer. Python zip magic for classes instead of tuples. NHibernate + Custom List: Unable to cast Easy way* to cast an object in a LINQ query? A simple test case I'm trying to get working: It's hard to answer this without a concrete use-case, but you may find it sufficient to simply cast to the non-generic IEnumerable interface. Filters a sequence of values based on a predicate. As for why your provided sample doesn't work: I still think var can make code more readable in some cases. 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