Q1071. Is it good to use arrow functions in render methods?
Yes, You can use. It is often the easiest way to pass parameters to callback functions. But you need to optimize the performance while using it. ```javascript class Foo e...
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Q1072. Is that possible to use expressions in switch cases?
You might have seen expressions used in switch condition but it is also possible to use for switch cases by assigning true value for the switch condition. Let's see the w...
Q1073. How do you say that state updates are merged?
When you call setState() in the component, React merges the object you provide into the current state. For example, let us take a facebook user with posts and comments de...
Q1074. How do you pass arguments to an event handler?
During iterations or loops, it is common to pass an extra parameter to an event handler. This can be achieved through arrow functions or bind method. Let us take an examp...
Q1075. How do style the console output using CSS?
You can add CSS styling to the console output using the CSS format content specifier %c. The console string message can be appended after the specifier and CSS style in a...
Q1076. How to prevent component from rendering?
You can prevent component from rendering by returning null based on specific condition. This way it can conditionally render component. ```javascript function Greeting(pr...
Q1077. What is nullish coalescing operator (??)?
It is a logical operator that returns its right-hand side operand when its left-hand side operand is null or undefined, and otherwise returns its left-hand side operand. ...
Q1078. How do you group and nest console output?
The `console.group()` can be used to group related log messages to be able to easily read the logs and use console.groupEnd()to close the group. Along with this, you can ...
Q1079. What is the difference between dense and sparse arrays?
An array contains items at each index starting from first(0) to last(array.length - 1) is called as Dense array. Whereas if at least one item is missing at any index, the...
Q1080. What is a consumer?
A Consumer is a React component that subscribes to context changes. It requires a function as a child which receives current context value as argument and returns a react...