The wrapping up of data and methods into a single unit (called class) is known as encapsulation. Encapsulation is a protection mechanism for the data members and methods present inside the class. In the encapsulation technique, we are restricting the data members from access to outside world end-user.
In PHP, encapsulation utilized to make the code more secure and robust. Using encapsulation, we are hiding the real implementation of data from the user and also does not allow anyone to manipulate data members except by calling the desired operation.
Variable pools are functional groupings of variables within Service Manager. There are currently four variable pools
A global variable is visible to the entire system. It begins with $G. or $lo..
A local variable is only visible to the RAD application in which it was defined. It begins with $L..
A parameter variable is defined on a parameter command panel. It may contain a value passed in from another application. By convention, parameter variables are written in uppercase letters, such as $PHASE or $GROUP.LIST. Parameter variables are invisible to the debugger.
A thread variable is only visible to the thread in which it was defined. The same variable in different threads has different values, even when the threads are spawned by the same parent.
Rich User Interface
- Lightweight, interpreted programming language
- Cross-platform compatible
- Integration with other backend and frontend technologies
- Used especially for the development of network-based applications
Properties can usually be changed, added, and deleted, but some are read only.
Writing into an HTML element, using innerHTML.
Writing into the HTML output using document.write().
Writing into an alert box, using window.alert().
Writing into the browser console, using console.log().
The let keyword was introduced in ES6 (2015).
Variables defined with let cannot be Redeclared.
Variables defined with let must be Declared before use.
Variables defined with let have Block Scope.
Temporal Dead Zone is a behaviour that occurs with variables declared using let and const keywords.
It is a behaviour where we try to access a variable before it is initialized.
A temporal dead zone (TDZ) is the area of a block where a variable is inaccessible until the moment the computer completely initializes it with a value.
Object destructuring is a new way to extract elements from an object or an array.