#Javascript interview questions how to
#Javascript interview questions code

How to detect the browser which is running the web page? We can use the checked property to check the status of the checkbox in JavaScript. How to check the status of checkboxes in JavaScript? We can use a navigator.appVersion property to find the Operating system on the client machine.Д¬onsole.log(navigator.appVersion) 29. How can I use JavaScript to find the Operating system on the client machine? Void(0) is used for preventing the page from refreshing or reloading. Mention the use of void(0) in JavaScript. It is also defined as a function that is passed as an argument to another function. Define callback function in JavaScript.ДЄ callback function is a function that is executed after the execution of another function. There are 3 different methods for defining variables in JavaScript:Дў6. What are the different methods for defining variables in JavaScript? It develops applications that run in a web browser.Дў5. It develops applications that run in a virtual machine or a web browser. JavaScript is an object-oriented scripting language used both client-side & server-side. Java is an object-oriented programming (OOP) language. Mention the differences between Java & JavaScript.

#Javascript interview questions code

How many different ways may JavaScript be included in an HTML file?ДЄ JavaScript code can be included in an HTML file in three distinct ways:Дў4.

Syntax for(let variableName in objectName) 23. The for-in loop in JavaScript is used for iterating through the properties of an object. What is the use of for-in loop in JavaScript? Unshift() method is an array method used for inserting an element at the beginning of an array. Push() method is an array method used for inserting an element at the end of an array.ДЇor example, const arr = What is the difference between push & unshift methods of an array in JavaScript? What are the methods for accessing & manipulating the document object model (DOM)?ДЎ5. It is a hierarchical representation of an HTML document. What is DOM in JavaScript?ДOM stands for Document Object Model. Typeof operator is used for checking the data type of a variable or value. What is the usage of typeof operator in JavaScript? It can be assigned to a variable to indicate that it currently has no value but will do so in the future. Null in JavaScript represents the absence of any value. In JavaScript, undefined signifies that a variable has been declared but not assigned a value or that it has not been declared at all. Mention the different types of pop-up boxes in JavaScript.Д¬onst value = confirm(вЂњDo you want to continue?вЂќ) What would be the output of the JavaScript code given below? console.log(5+3+'6') The style of a HTML element can be changed in 2 ways:Д®tAttriute(вЂstyleвЂ™, cssProperty) ДЇor example, tAttribute('style', 'background-color: yellow ') ДЇor example, ='yellow' ДЁ. How can the style of an HTML element be changed using JavaScript? It refers to the owner object in a method and the global object in a function.

Depending on where it is used, the вЂњthisвЂќ has multiple values. вЂthisвЂ™ keyword in JavaScript refers to the object from where it was called. In JavaScript, what do you mean by вЂњthisвЂќ keyword? It returns true if the given value is not a number, otherwise false. What is the usage of isNaN in JavaScript? Yes, because the data type of variables is decided at runtime, JavaScript is a dynamically typed language. Is JavaScript a dynamically typed language? вЂ=вЂ™ returns true if two values are same whereas вЂ=вЂ™ returns true if the data type & value of a variable are the same.