What will be the output of the following Javascript code?
<script>
var x = 10;
x *= 5;
document.getElementById("demo").innerHTML = x;
</script>
var x = 10;
x *= 5;
document.getElementById("demo").innerHTML = x;
</script>
5
10
50
Error
Correct Answer :
C. 50
Explanation: The *= operator is a shorthand expression for multiplication of a particular number. It is a combination of two operators * and = .
Related Questions
The var and function are __________
Keywords
Declaration statements
Data types
Prototypes
For the below mentioned code snippet:
var o = new Object();
The equivalent statement is:
var o = Object();
var o;
var o= new Object;
Object o=new Object();
The expression of calling (or executing) a function or method in JavaScript is called ________
Primary expression
Functional expression
Invocation expression
Property Access Expression
The var and function are __________
Keywords
Declaration statements
Data types
Prototypes
The snippet that has to be used to check if a is not equal to null is _________
if(a!=null)
if (!a)
if(a!null)
if(a!==null)
What will be the step of the interpreter in a jump statement when an exception is thrown?
The interpreter stops its work
The interpreter throws another exception
The interpreter jumps to the nearest enclosing exception handler
The interpreter throws an error
Which is a more efficient JavaScript code snippet?
Code 1 :
for(var num=10;num>=1;num--)
{
document.writeln(num);
}
Code 2 :
var num=10;
while(num>=1)
{
document.writeln(num);
num++;
}
{
document.writeln(num);
}
while(num>=1)
{
document.writeln(num);
num++;
}
Code 1
Code 2
Both Code 1 and Code 2
Cannot Compare
The function definitions in JavaScript begins with _____________
Identifier and Parentheses
Return type and Identifier
Return type, Function keyword, Identifier and Parentheses
Identifier and Return type
A linkage of series of prototype objects is called as ________
prototype stack
prototype chain
prototype class
prototypes
What will be the output of the following JavaScript code?
const obj = {prop: 12};
Object.preventExtensions(obj);
console.log( Object.isExtensible(obj));
Object.preventExtensions(obj);
console.log( Object.isExtensible(obj));
12
false
true
error
If you have a function f and an object o, you can define a method named m of o with
o.m=m.f;
o.m=f;
o=f.m;
o=f;
What will the following code snippet work? If not, what will be the error?
function tail(o)
{
for (; o.next; o = o.next) ;
return o;
}
{
for (; o.next; o = o.next) ;
return o;
}
No, this will throw an exception as only numerics can be used in a for loop
No, this will not iterate
Yes, this will work
No, this will result in a runtime error with the message Cannot use Linked List
What happens in the following javaScript code snippet?
var count = 0;
while (count < 10)
{
console.log(count);
count++;
}
while (count < 10)
{
console.log(count);
count++;
}
The values of count are logged or stored in a particular location or storage
The value of count from 0 to 9 is displayed in the console
An error is displayed
An exception is thrown
What will be the output of the following Javascript code?
var a= 0;
var b = 0;
while (a < 3)
{
a++;
b += a;
console.log(b);
}
var b = 0;
while (a < 3)
{
a++;
b += a;
console.log(b);
}
135
123
013
01
In the following switch syntax, the expression is compared with the case labels using which of the following operator(s)?
switch(expression)
{
statements
}
{
statements
}
==
equals
equal
===
What will be the output of the following Javascript code?
int size=5;
int a=5;
int size=4;
for(int j=size;j>=0;j--)
{
console.log(a);
a=a-2;
}
int a=5;
int size=4;
for(int j=size;j>=0;j--)
{
console.log(a);
a=a-2;
}
5555
5321
531-1
531
What will be the output of the following JavaScript code?
var person =
{
name: Rahul,
getName: function()
{
nreturn this.name;
}
}
var unboundName = person.getName;
var boundName = unboundName.bind(person);
document.writeln(boundName());
{
name: Rahul,
getName: function()
{
nreturn this.name;
}
}
var unboundName = person.getName;
var boundName = unboundName.bind(person);
document.writeln(boundName());
runtime error;
compilation error
Rahul
undefined
The enumeration order becomes implementation dependent and non-interoperable if ___________
If the object inherits enumerable properties
The object does not have the properties present in the integer array indices
The delete keyword is never used
Object.defineProperty() is not used
The generalised syntax for a real number representation is __________
[digits][.digits][(E|e)[(+|-)]digits]
[digits][+digits][(E|e)[(+|-)]digits]
[digits][(E|e)[(+|-)]digits]
[.digits][digits][(E|e)[(+|-)]digits]
What will be the output of the following JavaScript code?
Int a=1;
if(a>10)
{
document.write(10);
}
else
{
document.write(a);
}
if(a>10)
{
document.write(10);
}
else
{
document.write(a);
}
10
0
1
Undefined
What will be the output of the following Javascript code?
var arr = [7, 5, 9, 1];
var min = Math.min.apply(null, arr);
document.writeln(min);
var min = Math.min.apply(null, arr);
document.writeln(min);
7
5
1
9
The enumeration order becomes implementation dependent and non-interoperable if ___________
If the object inherits enumerable properties
The object does not have the properties present in the integer array indices
The delete keyword is never used
Object.defineProperty() is not used
A function with no return value is called ___________
Procedures
Method
Static function
Dynamic function
What will happen if the body of a for/in loop deletes a property that has not yet been enumerated?
The property will be stored in a cache
The loop will not run
That property will not be enumerated
The property will be enumerated
What will be the output of the following Javascript code?
var add=new Function(num1,num2,return num1+num2);
document.writeln(add(2,5));
document.writeln(add(2,5));
2
5
Error
7
The primary purpose of the array map() function is that it __________
maps the elements of another array into itself
passes each element of the array and returns the necessary mapped elements
passes each element of the array on which it is invoked to the function you specify, and returns an array containing the values returned by that function
pass the elements of the array into another array
What is a block statement in JavaScript?
conditional block
block that contains a single statement
both conditional block and a single statement
block that combines multiple statements into a single compound statement
Consider the following code snippet
function f(o)
{
if (o === undefined) debugger;
}
What could be the task of the statement debugger?
{
if (o === undefined) debugger;
}
It does nothing but a simple breakpoint
It debugs the error in that statement and restarts the statements execution
It is used as a keyword that debugs the entire program at once
It is used to find error in the statement
Which keyword is used to define the function in javascript?
void
int
function
main
What will be the output of the following JavaScript code?
var string1 = 123;
var intvalue = 123;
alert( string1 + intvalue );
var intvalue = 123;
alert( string1 + intvalue );
123246
246
123123
Exception