Tutorial by Examples: b

Delete in nedb

In order to remove documents in nedb, it's very easy. We just have to use remove function of db object. db.remove({ name: 'bigbounty' }, function (err, numremoved) { // numremoved is the number of documents that are removed. });

electron • Using nedb in electron

Show Tables

In order to view tables in a database, use the .tables command. Example: sqlite> .tables table1 table2 table3 table4 table5

sqlite3 • Getting started with sqlite3

Simple script for black-box integration test of console applications

This is a simple example on how you can automate tests for a console application that interact with standard input and standard output. The tested application read and sum every new line and will provide the result after a single white line is provided. The power shell script write "pass"...

PowerShell • Infrastructure Automation

Setup environment variable in ASP.NET Core [Windows]

=> Original Post <= ASP.NET Core uses the ASPNETCORE_ENVIRONMENT environment variable to determine the current environment. By default, if you run your application without setting this value, it will automatically default to the Production environment. > dotnet run Project TestApp (.NETC...

asp.net-core • Getting started with asp.net-core

How use ansible to install mysql binary file

hosts: mysql tasks: name: Add mysql user user: name: mysql shell: /sbin/nologin name: install the latest version of libselinux-python yum: name: libselinux-python state: latest name: install perl yum: name: perl state: latest name: remove the mysql-libs package y...

ansible • Ansible install mysql

Recommended ways to execute shell code in Ruby:

Open3.popen3 or Open3.capture3: Open3 actually just uses Ruby's spawn command, but gives you a much better API. Open3.popen3 Popen3 runs in a sub-process and returns stdin, stdout, stderr and wait_thr. require 'open3' stdin, stdout, stderr, wait_thr = Open3.popen3("sleep 5s && ls&q...

Ruby Language • Operating System or Shell commands

Clasic ways to execute shell code in Ruby:

Exec: exec 'echo "hello world"' or exec ('echo "hello world"') The System Command: system 'echo "hello world"' Will output "hello world" in the command window. or system ('echo "hello world"') The system command can return a true if ...

Ruby Language • Operating System or Shell commands

Get help on available mix tasks

To list available mix tasks use: mix help To get help on a specific task use mix help task e.g.: mix help cmd

Elixir Language • Mix

Keyboard Events

AttributeDescriptiononkeydownFires when a user is pressing a keyonkeypressFires when a user presses a keyonkeyupFires when a user releases a key

HTML • HTML Event Attributes

Finding an object's class

To find whether an object was constructed by a certain constructor or one inheriting from it, you can use the instanceof command: //We want this function to take the sum of the numbers passed to it //It can be called as sum(1, 2, 3) or sum([1, 2, 3]) and should give 6 function sum(...arguments) {...

JavaScript • Datatypes in Javascript

Faster multiplication or division by powers of 2

Shifting bits left (right) is equivalent to multiplying (dividing) by 2. It's the same in base 10: if we "left-shift" 13 by 2 places, we get 1300, or 13 * (10 ** 2). And if we take 12345 and "right-shift" by 3 places and then remove the decimal part, we get 12, or Math.floor(1234...

JavaScript • Bitwise Operators - Real World Examples (snippets)

HTML text in UILabel

NSString * htmlString = @"<html><body> <b> Example bold text in HTML </b> </body></html>"; NSAttributedString * attrStr = [[NSAttributedString alloc] initWithData:[htmlString dataUsingEncoding:NSUnicodeStringEncoding] options:@{ NSDocumentTypeDocumentAt...

iOS • attributedText in UILabel

Set different property to text in single UILabel

The first step you need to preform is to create a NSMutableAttributedString object. The reason we create a NSMutableAttributedString instead of NSAttributedString is because it enables us to append string to it. NSString *fullStr = @"Hello World!"; NSMutableAttributedString *attString =[...

iOS • attributedText in UILabel

Spring Boot and Spring Data Elasticsearch integration

In this example we are going to implement spring-data-elasticsearch project to store POJO in elasticsearch. We will see a sample maven project which does the followings: Insert a Greeting(id, username, message) item on elasticsearch. Get All Greeting items which have been inserted. Update a Gr...

spring-boot • Spring Boot + Spring Data Elasticsearch

Spring boot and spring data elasticsearch integration

In this example we are going to see a maven based spring boot application which integrates spring-data-elasticsearch. Here, we will do the followings and see the respective code segments. Insert a Greeting(id, username, message) item on elasticsearch. Get all items from elasticsearch Update a s...

spring-boot • Spring Boot + Spring Data Elasticsearch

Organizing new invoice numbers

Incrementing an invoice number and saving its value is a frequent task. Using CustomDocumentProperties (CDPs) is a good method to store such numbers in a relatively safe way within the same work book, but avoiding to show related cell values simply in an unprotected work sheet. Additional hint: A...

excel-vba • CustomDocumentProperties in practice

Delete local branches that have been deleted on the remote

To remote tracking between local and deleted remote branches use git fetch -p you can then use git branch -vv to see which branches are no longer being tracked. Branches that are no longer being tracked will be in the form below, containing 'gone' branch 12345e6 [origin/bran...

Git • Tidying up your local and remote repository

Convert blocking method to asynchonous

The following method will take a second or two depending on your connection to retrieve a web page and count the text length. Whatever thread calls it will block for that period of time. Also it rethrows an exception which is useful later on. public static long blockingGetWebPageLength(String urlS...

Java Language • CompletableFuture

Simple Example of CompletableFuture

In the example below, the calculateShippingPrice method calculates shipping cost, which takes some processing time. In a real world example, this would e.g. be contacting another server which returns the price based on the weight of the product and the shipping method. By modeling this in an async ...

Java Language • CompletableFuture

Simple coroutine which delay's 1 second but not blocks

(from official doc) fun main(args: Array<String>) { launch(CommonPool) { // create new coroutine in common thread pool delay(1000L) // non-blocking delay for 1 second (default time unit is ms) println("World!") // print after delay } println("He...

Kotlin • coroutines