That will work fine (no exception). Extension methods don’t use virtual calls (i.e. it uses the “call” il instruction, not “callvirt”) so there is no null check unless you write it yourself in the extension method. This is actually useful in a few cases: public static bool IsNullOrEmpty(this string value) { return string.IsNullOrEmpty(value); } public … Read more
There is already a foreach statement included in the language that does the job most of the time. I’d hate to see the following: list.ForEach( item => { item.DoSomething(); } ); Instead of: foreach(Item item in list) { item.DoSomething(); } The latter is clearer and easier to read in most situations, although maybe a bit … Read more
public static bool In<T>(this T source, params T[] list) { if(null==source) throw new ArgumentNullException(“source”); return list.Contains(source); } Allows me to replace: if(reallyLongIntegerVariableName == 1 || reallyLongIntegerVariableName == 6 || reallyLongIntegerVariableName == 9 || reallyLongIntegerVariableName == 11) { // do something…. } and if(reallyLongStringVariableName == “string1” || reallyLongStringVariableName == “string2” || reallyLongStringVariableName == “string3”) { // … Read more
No. Extension methods require an instance variable (value) for an object. You can however, write a static wrapper around the ConfigurationManager interface. If you implement the wrapper, you don’t need an extension method since you can just add the method directly. public static class ConfigurationManagerWrapper { public static ConfigurationSection GetSection( string name ) { return … Read more
If you are starting with something that has a .Length or .Count (such as ICollection<T>, IList<T>, List<T>, etc) – then this will be the fastest option, since it doesn’t need to go through the GetEnumerator()/MoveNext()/Dispose() sequence required by Any() to check for a non-empty IEnumerable<T> sequence. For just IEnumerable<T>, then Any() will generally be quicker, … Read more
IEnumerable<Customer> filteredList = originalList .GroupBy(customer => customer.CustomerId) .Select(group => group.First());
For the moment it is still not supported out of the box by Roslyn compiler … Until now, the extension properties were not seen as valuable enough to be included in the previous versions of C# standard. C# 7 and C# 8.0 have seen this as proposal champion but it wasn’t released yet, most of … Read more