Form field validations using regex javascript

What is a Regular Expression? As per wikipedia, A regular expression (shortened as regex or regexp; also referred to as rational expression) is a sequence of characters that specifies a search pattern. Create an index.html file where you can add all the form input fields as below. Add name property for the fields which will be accessed in the validation.js to perform regex validations. index.html validation.js …

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Validate a palindrome

A palindrome is a word, number, phrase, or other sequence of characters which reads the same backward as forward, such as madam or racecar.  Return True if it”s a palindrome and False if not palindrome

Docker Commands

Show commands & management commands Docker version info Show info like number of containers, etc WORKING WITH CONTAINERS Create an run a container in foreground Create an run a container in background Shorthand Naming Containers TIP: WHAT RUN DID Looked for image called nginx in image cache If not found in cache, it looks to …

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Design Patterns in PHP – Chain-of-responsibility pattern

Chain-of-responsibility pattern The chain-of-responsibility pattern is a behavioral design pattern consisting of a source of command objects and a series of processing objects. Each processing object contains logic that defines the types of command objects that it can handle; the rest are passed to the next processing object in the chain. A mechanism also exists …

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Design Patterns in PHP – Observer pattern

Observer pattern The observer pattern is a software design pattern in which an object, named the subject, maintains a list of its dependents, called observers, and notifies them automatically of any state changes, usually by calling one of their methods. It is mainly used for implementing distributed event handling systems, in “event driven” software. In …

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Design Patterns in PHP – Strategy pattern

Strategy pattern The strategy pattern (also known as the policy pattern) is a behavioral software design pattern that enables selecting an algorithm at runtime. Instead of implementing a single algorithm directly, code receives run-time instructions as to which in a family of algorithms to use. Strategy lets the algorithm vary independently from clients that use …

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Design Patterns in PHP – Decorator design pattern

The Decorator Pattern, Adapter Pattern, Template Method Pattern, Strategy Pattern, Observer Pattern Decorator design pattern In object-oriented programming, the decorator pattern is a design pattern that allows behavior to be added to an individual object, dynamically, without affecting the behavior of other objects from the same class. The decorator pattern is often useful for adhering …

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How to preserve array keys for an associative array in php

Insert an associtive array ain another assoInsert an associative array in another associative array array_splice() or array_merge() php functions doesn’t preserve keys. So if we use these functions then new array key will be [0]Instead we will use array_splice() and use ‘+’ to concatenate the arrays

Find the symmetric difference between arrays using javascript

Find the symmetric difference between arrays using javascript In mathematics, the symmetric difference of two sets, also known as the disjunctive union, is the set of elements which are in either of the sets, but not in their intersection. The mathematical term symmetric difference (△ or ⊕) of two sets is the set of elements …

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How to hide or show details using v-if and v-show directive in Vue JS

Conditional rendering can be achieved using v-ifConditional display can be achieved using v-show First create a vue project using vue cli Now change directory start the server Lets start building the VUE component inside src/components/showHide.vue Remove HelloWorld.vue component and register showHide.vue component in App.vue Your showHide.vue component will look like this:

How to check Vue js version

There are few ways to check vue js version: npm v vue run this on the terminal Check package.json, code will be something like this If you have vue dev tools installed then go to the Vue tab and you should be able to see the version there

Measure execution time of a function using javascript

You can measure the performance of javascript code using console.time() function. This can be helpful in debugging and optimizing code which is taking lot of memory. console.time() can be used with console.timeEnd(). console.timeEnd() function tells console to stop calculating the time. You will see result as below: Running loop :0 timesRunning loop :1 timesRunning loop …

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