How does TypeOf Operator work?
The typeof operator is used to get the data type of its operand. The operand can be either a literal or a data structure such as a variable, a function, or an object. It is a unary operator that is placed before its single operand, which can be of any type. Its value is a string indicating the data type of the operand.
When should I use Arrow Functions in ES6?
‘m now using the following rule of thumb for functions in ES6 and beyond:
- Use function in the global scope and for Object.prototype properties.
- Use class for object constructors.
- Use => everywhere else.
Why use arrow functions almost everywhere?
- Scope safety: When arrow functions are used consistently, everything is guaranteed to use the same thisObject as the root. If even a single standard function callback is mixed in with a bunch of arrow functions there’s a chance the scope will become messed up.
- Compactness: Arrow functions are easier to read and write. (This may seem opinionated so I will give a few examples further on).
- Clarity: When almost everything is an arrow function, any regular function immediately sticks out for defining the scope. A developer can always look up the next-higher function statement to see what the thisObject is.
What is the definition of global variables? In what way, these variables are declared?
What is the definition of the prompt box?
What is Callback?
- Run time errors- errors occurred due to misrepresentation of HTML commands.
- Load time errors- errors that occurred at the time of web page loading are known as load time errors. These errors may occur due to improper syntaxes
- Logical errors- logical errors may occur due to improper logical performance of the function.
Timers are used to execute a piece of code at a set time or repeat the code in a given interval. This is done by using the functions setTimeout, setInterval, and clearInterval.
The setTimeout(function, delay) function is used to start a timer that calls a particular function after the mentioned delay. The setInterval(function, delay) function repeatedly executes the given function in the mentioned delay and only halts when canceled. The clearInterval(id) function instructs the timer to stop.
Timers are operated within a single thread, and thus events might queue up, waiting to be executed.
Cookies are the small test files stored in a computer, and they get created when the user visits the websites to store information that they need. Examples could be User Name details and shopping cart information from previous visits.
The pop() method is similar to the shift() method, but the difference is that the Shift method works at the array’s start. The pop() method takes the last element off of the given array and returns it. The array on which it is called is then altered.
Is it possible to remove the content from a website? If yes, how?
Yes, there are a few possible ways to remove content from the website at will.
Another way to do so is by removing the element node corresponding to the content. This technique completely removes the data from the webpage as well as the code. We can do this by .removeChild() method. Or if we are dealing with an array (including a NodeList), then we can easily empty the array, and get the same result.
The decision of selecting the appropriate method for the situation depends on the programmer and his/ her needs.