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Customer[] customers = Customers.ToArray(); Purchase[] purchases = Purchases.ToArray(); var groupJoinQuery = from c in customers join p in purchases on c.ID equals p.CustomerID into custPurchases select new { CustName = c.Name, custPurchases }; ...

An interesting thing to note which may help optimize your applications is that primitives are actually also refcounted under the hood. Let's take a look at numbers; for all integers between -5 and 256, Python always reuses the same object: >>> import sys >>> sys.getrefcount(1) 7...

>>> import sys >>> a = object() >>> sys.getrefcount(a) 2 >>> b = a >>> sys.getrefcount(a) 3 >>> del b >>> sys.getrefcount(a) 2

var myData = [ { name: "test1", value: "ok" }, { name: "test2", value: "nok" } ] // We have to select elements (here div.samples) // and assign data. The second parameter of data() is really important, // it will determine the "key" t...

When you bind a service to your application credentials become available through the VCAP_SERVICES environment variable. This environment variable contains JSON containing the credentials for all bound services. Example VCAP_SERVICES environment variable { "push-reappt": [ { ...

String#replace can have a function as its second argument so you can provide a replacement based on some logic. "Some string Some".replace(/Some/g, (match, startIndex, wholeString) => { if(startIndex == 0){ return 'Start'; } else { return 'End'; } }); // will retur...

#include <SoftwareSerial.h> // its always better to change the default tx and rx as the may interfere with other process in future. // configure tx , rx by defualt they will be 0 and 1 in arduino UNO SoftwareSerial blue(3,2); void setup() { // preferred baud rate/data transfer rat...

app.js angular.module('myApp', ['ui.router']) .controller('controllerOne', function() { this.message = 'Hello world from Controller One!'; }) .controller('controllerTwo', function() { this.message = 'Hello world from Controller Two!'; }) .controller('controllerThree', funct...

Syntax Syntax: log_format name string ...; Syntax: access_log path [format [buffer=size] [gzip[=level]] [flush=time] [if=condition]]; access_log off; Using them together log_format compression '$remote_addr - $remote_user [$time_local] ' '"$request" $status...

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) { ...

To enable a certain CORS policy for specific controllers you have to build the policy in the AddCors extension within the ConfigureServices method: services.AddCors(cors => cors.AddPolicy("AllowAll", policy => { policy.AllowAnyOrigin() .AllowAnyMethod() ...

Open the psql command line tool connected to the database where your table is. Then type the following command: \d tablename To get extended information type \d+ tablename If you have forgotten the name of the table, just type \d into psql to obtain a list of tables and views in the current ...

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...

Let's say we have a simple table called person: CREATE TABLE person ( person_id BIGINT, name VARCHAR(255). age INT, city VARCHAR(255) ); The most basic insert involves inserting all values in the table: INSERT INTO person VALUES (1, 'john doe', 25, 'new york'); If you wa...

You can also apply a mixin globally. Use caution! Once you apply a mixin globally, it will affect every Vue instance created afterwards. When used properly, this can be used to inject processing logic for custom options: // inject a handler for `myOption` custom option Vue.mixin({ created: func...

Mixins are a flexible way to distribute reusable functionalities for Vue components. A mixin object can contain any component options. When a component uses a mixin, all options in the mixin will be “mixed” into the component’s own options. // define a mixin object var myMixin = { created: fun...

To change the appearance of the keyboard, the following types can be set individually on every UITextFields property: keyboardType typedef NS_ENUM(NSInteger, UIKeyboardType) { UIKeyboardTypeDefault, // Default type for the current input method. UIKeyboardTypeASCIICapable, ...

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;

If you have a variable declared before, you can assign some value to it: For example: int a; // declared previously a = 2; Or change the value: int a = 3; // initalized previously a = 2;

char : signed 1-byte character value byte : unsigned 8-bit integer int : signed 16-bit (on ATMEGA based boards) or 32-bit (on Arduino Due) integer unsigned int : unsigned 16-bit (on ATMEGA based boards) or 32-bit (on Arduino Due) integer long : signed 32-bit integer unsigned long : unsigned 3...