This is probably one of those rare cases where it makes sense to use an extern alias. In the properties page for the reference to System.Core (i.e. under References, select System.Core, right-click and select “Properties”), change the “Aliases” value to “global,SystemCore” (or just “SystemCore” if it’s blank to start with). Then in your code, write: … Read more
It really depends on what you mean by “mixin” – everyone seems to have a slightly different idea. The kind of mixin I’d like to see (but which isn’t available in C#) is making implementation-through-composition simple: public class Mixin : ISomeInterface { private SomeImplementation impl implements ISomeInterface; public void OneMethod() { // Specialise just this … Read more
This question & answer lead me to believe that IQueryable require an active context for its operation. That means you should try this instead: try { IQueryable<User> users; using (var dataContext = new dataContext()) { users = dataContext.Users.Where(x => x.AccountID == accountId && x.IsAdmin == false); if(users.Any() == false) { return null; } else { … Read more
It seems there are two use-cases of why you may want to do what you are doing. In the first use-case, Swift will allow you to do what you want, but not very cleanly in the second use-case. I’m guessing you fall into the second category, but I’ll go through both. Extending the functionality of … Read more
Extension methods only work on instances, so it can’t be done, but with some well-chosen class/method names and generics, you can produce a result that looks just as good: public class SelectList { // Normal SelectList properties/methods go here public static SelectList Of<T>() { Type t = typeof(T); if (t.IsEnum) { var values = from … Read more
Since you cannot extend string.Trim(). You could make an Extension method as described here that trims and reduces whitespace. namespace CustomExtensions { //Extension methods must be defined in a static class public static class StringExtension { // This is the extension method. // The first parameter takes the “this” modifier // and specifies the type … Read more
This is not possible. To explain why, first read my essay on why it is that we optimize deallocation of local variables of value type by putting them on the stack: https://web.archive.org/web/20100224071314/http://blogs.msdn.com/ericlippert/archive/2009/05/04/the-stack-is-an-implementation-detail-part-two.aspx Now that you understand that, it should be clear why you cannot store a “ref bool” in an array. If you could, then … Read more
They have totally different semantics. AddRange modifies the list by adding the other items to it. Concat returns a new sequence containing the list and the other items, without modifying the list. Choose whichever one has the semantics you want.
Honestly, sometimes it can be situational once you start using Funcs and Actions. Say you are using these three funcs: Func<DataClasses.User, String> userName = user => user.UserName; Func<DataClasses.User, Boolean> userIDOverTen = user => user.UserID < 10; Func<DataClasses.User, Boolean> userIDUnderTen = user => user.UserID > 10; As you can see the first one replaces the lamdba … Read more
Creating an extension Add a new swift file with File > New > File… > iOS > Source > Swift File. You can call it what you want. The general naming convention is to call it TypeName+NewFunctionality.swift. Example 1 – Double Double+Conversions.swift import Swift // or Foundation extension Double { func celsiusToFahrenheit() -> Double { … Read more