SEARCH KEYWORD -- Object creation
malloc/free and new/delete in C++
malloc and free are C++/C language standard library functions, while new/delete are operator of C++. They can be used to allocate dynamic memory and free memory in C++ programs malloc/free can not meet the requirements of dynamic objects creation. Object needs to call the constructor to initialize the object when creating, the object needs to call the destructor before it is destroyed Since malloc() and free() are library functions rather than operators, the compiler has no control permiss...
Extension context menu is missing in Firefox after restart
If you have experience of writing Chrome extension, you may be familiar with how you can add a context menu for your extension. The code would be similar to below: chrome.runtime.onInstalled.addListener(function() { chrome.contextMenus.removeAll(); chrome.contextMenus.create({ "id": "your_id", "title": "Your Title", "contexts": ["all"] }); }); You need to add a listener listening to the extension install event. Once the extension is installed, create a contex...
CHROME,FIREFOX,EXTENSION,CONTEXT MENU 2018-11-16 20:58:20
this in JavaScript
this is a keyword in JavaScript. It refers to an internal object created automatically when a function executes, it can only be used in a function. For example: function test(){     this.x = 1;   }The this keyword will change when a function is called in different situations. However, the general rule is : this refers to the object which calls the function.Next we discuss the use of this in 4 different situatio...
this,keyword,use,JavaScript 2012-05-05 12:47:37
Ways to check existence of JavaScript object
The design of JavaScript is not so sophisticated. It's very easy for us to make mistakes if we are not very careful when using JavaScript. For example, to check the existence of JavaScript object. Now we want to check whether a global object myObj exists or not, if it doesn't exist, we declare it. The pseudo code for this is : if(myObj not exist){ declare myObj; } You may think it's very easy to write the code. In fact, it is much more difficult than we may think. Juriy Zaytsev says there are m...
JAVASCRIPT,OBJECT,EXISTENCE 2020-09-12 02:14:02
static nested and non-static nested class in Java
Nested classes are divided into two categories: static and non-static(inner). Nested classes that are declared static are simply called static nested classes. Non-static nested classes are called inner classes. Static class can be defined as : class OuterClass{ static class StaticNestedClass{ //OTHER STUFF } } Static nested classes are accessed using the enclosing class name: OuterClass.StaticNestedClass For example, to create an object for the static nested class, use this synta...
Java,static nested class,inner class 2014-04-23 07:11:44
Python object creation sequence
[The Python version described in this article is 3.x] This article aims to explore the process of creating new objects in Python. As I explained in a previous article, object creation is just a special case of calling a callable. Consider this Python code: class Joe: pass j = Joe() What happens when j = Joe() is executed? Python sees it as a call to the callable Joe, and routes it to the internal function PyObject_Call, with Joe passed as the first argument. PyObject_Call looks at the ty...
Python,Object creation 2012-04-16 15:03:55
JavaScript: Passing by Value or by Reference
In JavaScript, we have functions and we have arguments that we pass into those functions. But how JavaScript handles what you’re passing in is not always clear. When you start getting into object-oriented development, you may find yourself perplexed over why you have access to values sometimes but not other times. When passing in a primitive type variable like a string or a number, the value is passed in by value. This means that any changes to that variable while in the function are com...
JavaScript,Function,Pass by reference,Pa 2011-07-28 11:05:25
+ operation on JavaScript objects
In JavaScript, there are two types of values: primitive and object. Primitives consist undefined, null, boolean, number and string. Other values such as array and function are objects. When applying + operation on different type of values, there would be three kinds of type conversion. Primitive conversion Number conversion String conversion There three type conversions have corresponding abstract operations in JavaScript: ToPrimitive(), ToNumber(), ToString(). For number additi...
JAVASCRIPT,PROGRAMMING 2018-10-12 22:19:12
JavaScript-style object literals in PHP
The object literal notation in JavaScript looks like: var fido = {name: "Fido", barks: true}; or var fido = {}; fido.name = "Fido"; fido.barks = true; From assoc arrays to objects In PHP you would call that an associative array. $fido = array( 'name' => "Fido", 'barks' => true ); And you can easily make it an object too: $fido = (object)$fido; echo gettype($fido); // "object" Or if you want to start with a blank object and add stuff to it: $fido = (object)array(); or $fido...
PHP,JavaScript,Object,Function call,Self vs this 2011-11-30 11:11:45
A small trick on using console.log to print data in JavaScript
When debugging JavaScript application, one may frequently use console.log to print data so that it is easy to debug when issue occurs and also helps on understand the data flow. The common way of printing a variable would be something like. let user = { name: "test" }; console.log(user); In this case it will print: { name: 'test' } This is OK when there is no much logging or the program is not complicated. But it becomes difficult to debug if there are lots of variables to be printed ...
JAVASCRIPT,CONSOLE.LOG,DEBUGGING 2019-09-03 10:24:24
RECENT
- What Is The Best SaaS CRM In 2024?
- Common Pitfalls When Handling JSON in Golang
- Streamlining the Project Invoicing Process: Tools and Strategies
- Performance comparison of string concatenation in Go language
- Why init() is not recommended in Go
- The Role of Coding Skills in Advancing Tech Careers
- Tips for Socializing With Friends During College
- Proximity Cards Do More Than Just Open Doors
- How to choose quality painted auto parts
- Oval engagement rings from MoonOcean: Elegance of form and individual approach
- more>>