Tutorial by Examples: re

Filters format the value of an expression for display to the user. They can be used in view templates, controllers or services. This example creates a filter (addZ) then uses it in a view. All this filter does is add a capital 'Z' to the end of the string. example.js angular.module('main', []) ...

Use the UseCors() extension method on the IApplicationBuilder in the Configure method to apply the CORS policy to all requests. public void ConfigureServices(IServiceCollection services) { services.AddMvc(); services.AddCors(); } public void Configure(IApplicationBuilder app) { ...

The policy builder allows you to build sophisticated policies. app.UseCors(builder => { builder.WithOrigins("http://localhost:5000", "http://myproductionapp.com") .WithMethods("GET", "POST", "HEAD") .WithHeaders(&quo...

Let's say you have a table called person: CREATE TABLE person ( person_id BIGINT NOT NULL, last_name VARCHAR(255) NOT NULL, first_name VARCHAR(255), age INT NOT NULL, PRIMARY KEY (person_id) ); You can create a new table of people over 30 like this: CREATE TABLE p...

Date always have a different format, they can be parsed using a specific parse_dates function. This input.csv: 2016 06 10 20:30:00 foo 2016 07 11 19:45:30 bar 2013 10 12 4:30:00 foo Can be parsed like this : mydateparser = lambda x: pd.datetime.strptime(x, "%Y %m %d %H:%M:%S...

Redux is the most common state management library used with React-Native. The following example demonstrates how to use the fetch API and dispatch changes to your applications state reducer using redux-thunk. export const fetchRecipes = (action) => { return (dispatch, getState) => { f...

You can inject any type of resource, Strings, Animations, Drawables, etc. To inject your first resource into an activity, you'll need to: Inherit from RoboActivity Annotate your resources with @InjectResource Example @InjectResource(R.string.app_name) String name; @InjectResource(R.drawa...

To create a variable: variableType variableName; For example: int a; To create a variable and initialize it: variableType variableName = initialValue; For example: int a = 2;

DECLARE @Employees TABLE ( EmployeeID INT NOT NULL PRIMARY KEY, FirstName NVARCHAR(50) NOT NULL, LastName NVARCHAR(50) NOT NULL, ManagerID INT NULL ) When you create a normal table, you use CREATE TABLE Name (Columns) syntax. When creating a table variable, you use DECLARE @...

DECLARE @Var1 INT = 5, @Var2 NVARCHAR(50) = N'Hello World', @Var3 DATETIME = GETDATE()

You can group related assertions in deftest unit tests within a context using the testing macro: (deftest add-nums (testing "Positive cases" (is (= 2 (+ 1 1))) (is (= 4 (+ 2 2)))) (testing "Negative cases" (is (= -1 (+ 2 -3))) (is (= -4 (+ 8 -12))))) ...

The are macro is also part of the clojure.test library. It allows you to make multiple assertions against a template. For example: (are [x y] (= x y) 4 (+ 2 2) 8 (* 2 4)) => true Here, (= x y) acts as a template which takes each argument and creates an is assertion out of it. Thi...

Input table data (People table) IdNameAge1John232Jane31 Query SELECT Id, Name, Age FROM People FOR JSON PATH Result [ {"Id":1,"Name":"John","Age":23}, {"Id":2,"Name":"Jane","Age":31} ]

Let's say we wish to write Euclid's gcd() as a lambda. As a function, it is: int gcd(int a, int b) { return b == 0 ? a : gcd(b, a%b); } But a lambda cannot be recursive, it has no way to invoke itself. A lambda has no name and using this within the body of a lambda refers to a captured thi...

Some API calls return a single failure/success flag, without any additional information (e.g. GetObject): if ( GetObjectW( obj, 0, NULL ) == 0 ) { // Failure: no additional information available. }

In addition to a failure/success return value, some API calls also set the last error on failure (e.g. CreateWindow). The documentation usually contains the following standard wording for this case: If the function succeeds, the return value is <API-specific success value>. If the function...

Some API calls can succeed or fail in more than one way. The APIs commonly return additional information for both successful invocations as well as errors (e.g. CreateMutex). if ( CreateMutexW( NULL, TRUE, L"Global\\MyNamedMutex" ) == NULL ) { // Failure: get additional information. ...

HRESULTs are numeric 32-bit values, where bits or bit ranges encode well-defined information. The MSB is a failure/success flag, with the remaining bits storing additional information. Failure or success can be determined using the FAILED or SUCCEEDED macros. HRESULTs are commonly used with COM, but...

CSS body { counter-reset: item-counter; /* create the counter */ } .item { counter-increment: item-counter; /* increment the counter every time an element with class "item" is encountered */ } .item-header:before { content: counter(item-counter) ". "; /* print the v...

function createNewFolderInGoogleDrive(folderName) { return DriveApp.createFolder(folderName); } Use function createNewFolderInGoogleDrive to create folder named Test folder in a Google Drive root: var newFolder = createNewFolderInGoogleDrive('Test folder'); newFolder has Class Folder typ...