JavaScript Interview Questions（1）

叁歲伎倆 2023-09-25 18:49 128阅读 0赞

# 1.What is JavaScript? #

*  JavaScript is a scripting language.
 *  It is different from Java language.
 *  It is object-based, lightweight, cross-platform translated language.
 *  It is widely used for `client-side validation`.
 *  The JavaScript Translator (embedded in the browser) is responsible for translating the JavaScript code for the web browser.

# 2. List some features of JavaScript. #

*  Lightweight
 *  Interpreted programming language
 *  Good for the applications which are network-centric
 *  Complementary to Java
 *  Complementary to HTML
 *  Open source

# 3. List some of the advantages of JavaScript. #

*  Server interaction is less
 *  Feedback to the visitors is immediate
 *  Interactivity is high
 *  Interfaces are richer

# 4.List some of the disadvantages of JavaScript. #

*  No support for multithreading
 *  No support for `multiprocessing`
 *  Reading and writing of files is not allowed
 *  No support for networking applications.

# 5.Define a named function in JavaScript. #

The function which has named at the time of definition is called a named function.

function msg()  
    {
          
      document.writeln("Named Function");  
    }  
    msg();

# 6.Name the types of functions #

*  `Named` \- These type of functions contains name at the time of definition.

function display()  
    {
          
      document.writeln("Named Function");  
    }  
    display();

*  `Anonymous` \- These type of functions doesn’t contain any name. They are declared dynamically at runtime.

var display=function()  
    {
          
      document.writeln("Anonymous Function");  
    }  
    display();

# 7.Define anonymous function #

*  It is a function that has no name.
 *  These functions are declared `dynamically` at `runtime` using the function operator instead of the function declaration.
 *  `The function operator` is more flexible than `a function declaration`.
 *  It can be easily used in the place of an expression.

# 8.Can an anonymous function be assigned to a variable? #

Yes, you can`assign an anonymous function` to `a variable`.

# 9. In JavaScript what is an argument object? #

The variables of JavaScript represent the arguments that are passed to a function.

# 10.Define closure. #

*  In JavaScript, we need `closures` when `a variable which is defined outside the scope`in reference is accessed from some inner scope.

var num = 10;  
    function sum()   
    {
          
    document.writeln(num+num);  
    }   
    sum();