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dynamic foo = 123; Console.WriteLine(foo + 234); // 357 Console.WriteLine(foo.ToUpper()) // RuntimeBinderException, since int doesn't have a ToUpper method foo = "123"; Console.WriteLine(foo + 234); // 123234 Console.WriteLine(foo.ToUpper()): // NOW A STRING

using System; public static void Main() { var value = GetValue(); Console.WriteLine(value); // dynamics are useful! } private static dynamic GetValue() { return "dynamics are useful!"; }

using System; using System.Dynamic; dynamic info = new ExpandoObject(); info.Id = 123; info.Another = 456; Console.WriteLine(info.Another); // 456 Console.WriteLine(info.DoesntExist); // Throws RuntimeBinderException

You can use a colon and the standard numeric format syntax to control how numbers are formatted. var decimalValue = 120.5; var asCurrency = $"It costs {decimalValue:C}"; // String value is "It costs $120.50" (depending on your local currency settings) var withThreeDecimal...

Expressions in C++ are assigned a particular value category, based on the result of those expressions. Value categories for expressions can affect C++ function overload resolution. Value categories determines two important-but-separate properties about an expression. One property is whether the exp...

Background TypeScript is a typed superset of JavaScript that compiles directly to JavaScript code. TypeScript files commonly use the .ts extension. Many IDEs support TypeScript without any other setup required, but TypeScript can also be compiled with the TypeScript Node.JS package from the command...

In this example, we illustrate string manipulation in MATLAB MEX. We will create a MEX-function that accepts a string as input from MATLAB, copy the data into C-string, modify it and convert it back to mxArray returned to the MATLAB side. The main objective of this example is to show how strings ca...

Since anonymous types are not named, variables of those types must be implicitly typed (var). var anon = new { Foo = 1, Bar = 2 }; // anon.Foo == 1 // anon.Bar == 2 If the member names are not specified, they are set to the name of the property/variable used to initialize the object. int foo ...

Anonymous types allow the creation of objects without having to explicitly define their types ahead of time, while maintaining static type checking. var anon = new { Value = 1 }; Console.WriteLine(anon.Id); // compile time error Conversely, dynamic has dynamic type checking, opting for runtime ...

Generic methods allow the use of anonymous types through type inference. void Log<T>(T obj) { // ... } Log(new { Value = 10 }); This means LINQ expressions can be used with anonymous types: var products = new[] { new { Amount = 10, Id = 0 }, new { Amount = 20, Id = 1 }, ...

Using generic constructors would require the anonymous types to be named, which is not possible. Alternatively, generic methods may be used to allow type inference to occur. var anon = new { Foo = 1, Bar = 2 }; var anon2 = new { Foo = 5, Bar = 10 }; List<T> CreateList<T>(params T[] it...

Anonymous type equality is given by the Equals instance method. Two objects are equal if they have the same type and equal values (through a.Prop.Equals(b.Prop)) for every property. var anon = new { Foo = 1, Bar = 2 }; var anon2 = new { Foo = 1, Bar = 2 }; var anon3 = new { Foo = 5, Bar = 10 }; ...

Arrays of anonymous types may be created with implicit typing. var arr = new[] { new { Id = 0 }, new { Id = 1 } };

To remove a cookie, set the expiry timestamp to a time in the past. This triggers the browser's removal mechanism: setcookie('user', '', time() - 3600, '/'); When deleting a cookie make sure the path and domain parameters of setcookie() matches the cookie you're trying to delete or a new cooki...

A view can filter some rows from the base table or project only some columns from it: CREATE VIEW new_employees_details AS SELECT E.id, Fname, Salary, Hire_date FROM Employees E WHERE hire_date > date '2015-01-01'; If you select form the view: select * from new_employees_details IdFNam...

A view can be a really complex query(aggregations, joins, subqueries, etc). Just be sure you add column names for everything you select: Create VIEW dept_income AS SELECT d.Name as DepartmentName, sum(e.salary) as TotalSalary FROM Employees e JOIN Departments d on e.DepartmentId = d.id GROUP BY...

round Rounds the value to the nearest whole number with x.5 rounding up (but note that -x.5 rounds down). round(3.000) // 3 round(3.001) // 3 round(3.499) // 3 round(3.500) // 4 round(3.999) // 4 round(-3.000) // -3 round(-3.001) // -3 round(-3.499) // -3 round(-3.500) // -4 *** careful...

arc4random_uniform(someNumber: UInt32) -> UInt32 This gives you random integers in the range 0 to someNumber - 1. The maximum value for UInt32 is 4,294,967,295 (that is, 2^32 - 1). Examples: Coin flip let flip = arc4random_uniform(2) // 0 or 1 Dice roll let roll = arc4random_...

What is Serialization Serialization is the process of converting an object's state (including its references) to a sequence of bytes, as well as the process of rebuilding those bytes into a live object at some future time. Serialization is used when you want to persist the object. It is also used b...

If you have cloned a fork (e.g. an open source project on Github) you may not have push access to the upstream repository, so you need both your fork but be able to fetch the upstream repository. First check the remote names: $ git remote -v origin https://github.com/myusername/repo.git (fetch...