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Element operations return a single, specific element from a sequence. ElementAt Returns the element at a specified index in a collection. Method Syntax // ElementAt var strings = new string[] { "zero", "one", "two", "three" }; var str = strings.E...

In a normal mathematical coordinate system, the point x=0, y=0 is at the lower left corner of the graph. But in the SVG coordinate system, this (0,0) point is at the top left corner of the ‘canvas’, it is sort of similar to CSS when you specify the position to absolute/fix and use top and left to co...

To generate an ActiveRecord model that automagically creates the correct db migrations & boilerplate test files for your model, enter this command rails generate model NAME column_name:column_type 'NAME' is the name of the model. 'field' is the name of the column in the DB table and 'type' i...

Components in Vue are like widgets. They allow us to write reusable custom elements with desired behavior. They are nothing but objects which can contain any/all of the options that the root or any Vue instance can contain, including an HTML template to render. Components consist of: HTML marku...

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...

CREATE TABLE #TEST ( Id INT, Name VARCHAR(10) ) Insert Into #Test select 1,'A' Union All Select 1,'B' union all Select 1,'C' union all Select 2,'D' Below is the output of above table,As you can see Id Column is repeated three times.. Id Name 1 A 1 B 1 C 2 D Now...

nginx consists of modules which are controlled by directives specified in the configuration file. Simple Directives A simple directive consists of the name and parameters separated by spaces and ends with a semicolon (;). Block Directive A block directive has the same structure as a simple direc...

Stream is especially useful when you want to run multiple operations on a collection. This is because Stream is lazy and only does one iteration (whereas Enum would do multiple iterations, for example). numbers = 1..100 |> Stream.map(fn(x) -> x * 2 end) |> Stream.filter(fn(x) -> rem(x...

You can add your own validations adding new classes inheriting from ActiveModel::Validator or from ActiveModel::EachValidator. Both methods are similar but they work in a slightly different ways: ActiveModel::Validator and validates_with Implement the validate method which takes a record as an arg...

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...

To get SSIS working for a SQL Server 2005 environment Acquire SQL Server 2005 (x86 or 64 bit) images. Mount the second disk and launch the installation wizard "Next" your way through the dialogs until you see see this screen. Under Client Components, ensure Business Intelligence De...

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...

Intellij IDEA attempts to appeal to the wide Java fanbase which uses Eclipse for their development by allowing developers to migrate their Eclipse projects over to an IDEA structure with a few simple clicks! First, start IDEA and click Import Project from the startup window: Then, select your Ec...

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...

Create a YAML file in the config/ directory, for example: config/neo4j.yml The content of neo4j.yml can be something like the below (for simplicity, default is used for all environments): default: &default host: localhost port: 7474 username: neo4j password: root development: ...

Navigator is React Native's default navigator. A Navigator component manages a stack of route objects, and provides methods for managing that stack. <Navigator ref={(navigator) => { this.navigator = navigator }} initialRoute={{ id: 'route1', title: 'Route 1' }} renderScene={this.ren...

Beware that numbers can accidentally be converted to strings or NaN (Not a Number). JavaScript is loosely typed. A variable can contain different data types, and a variable can change its data type: var x = "Hello"; // typeof x is a string x = 5; // changes typeof x to...

When custom options are merged, they use the default strategy, which simply overwrites the existing value. If you want a custom option to be merged using custom logic, you need to attach a function to Vue.config.optionMergeStrategies: Vue.config.optionMergeStrategies.myOption = function (toVal, fro...

Add the following pom to the dependencies section of your gradle build file : project.dependencies { compile 'org.roboguice:roboguice:3.+' provided 'org.roboguice:roboblender:3.+' }

The @ContentView annotation can be used to further alleviate development of activities and replace the setContentView statement : @ContentView(R.layout.myactivity_layout) public class MyActivity extends RoboActivity { @InjectView(R.id.text1) TextView textView; @Override protected ...