What will be the output of the following Javascript code?
<script>
document.getElementById("demo").innerHTML = typeof "John"
</script>
document.getElementById("demo").innerHTML = typeof "John"
</script>
integer
number
string
error
Correct Answer :
C. string
Explanation: The typeof operator returns the type of the argument passed to it. The typeof operator returns number for an integer and string for a character array.
Related Questions
What will be the output of the following JavaScript code?
int a=4;
int b=1;
int c=0;
If(a==b)
document.write(a);
else if(a==c)
document.write(a);
else
document.write(c);
int b=1;
int c=0;
If(a==b)
document.write(a);
else if(a==c)
document.write(a);
else
document.write(c);
4
1
Error
0
The object has three object attributes namely ________
Class, parameters, objects extensible flag
Prototype, class, objects parameters
Prototype, class, objects extensible flag
Native object, Classes and Interfaces and Objects extensible flag
The web development environment (JavaScript) offers which standard construct for data validation of the input entered by the user.
Controlled loop constructs
Case checking constructs
Validation constructs
All of the mentioned
When an empty statement is encountered, a JavaScript interpreter __________
Ignores the statement
Prompts to complete the statement
Throws an error
Shows a warning
The expression of calling (or executing) a function or method in JavaScript is called ________
Primary expression
Functional expression
Invocation expression
Property Access Expression
What will be the output of the following Javascript code?
<script>
document.getElementById("demo").innerHTML = typeof "John"
</script>
document.getElementById("demo").innerHTML = typeof "John"
</script>
integer
number
string
error
What will be the output of the following Javascript code?
var a = 10;
do {
a += 1;
console.log(a);
} while (a < 5);
do {
a += 1;
console.log(a);
} while (a < 5);
11121314
1112
12345
11
What will be the output of the following JavaScript code?
const obj1 =
{
property1: 21
}
const descriptor1 = Object.getOwnPropertyDescriptor(obj1, 'property1');
console.log(descriptor1.configurable);
console.log(descriptor1.enumerable);
{
property1: 21
}
const descriptor1 = Object.getOwnPropertyDescriptor(obj1, 'property1');
console.log(descriptor1.configurable);
console.log(descriptor1.enumerable);
true 21
true false
true true
false false
What will be the output of the following JavaScript code?
var grade='A';
var result;
switch(grade)
{
case 'A':
result+=10;
case 'B':
result+= 9;
case 'C':
result+= 8;
default:
result+= 0;
}
document.write(result);
var result;
switch(grade)
{
case 'A':
result+=10;
case 'B':
result+= 9;
case 'C':
result+= 8;
default:
result+= 0;
}
document.write(result);
10
27
8
0
A JavaScript program developed on a Unix Machine ________
will throw errors and exceptions
must be restricted to a Unix Machine only
will work perfectly well on a Windows Machine
will be displayed as a JavaScript text on the browser
Assume that we have to convert false that is a non-string to string. The command that we use is (without invoking the new operator).
false.toString()
String(false)
String newvariable=false
Both false.toString() and String(false)
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
What will be the output of the following JavaScript code?
function info()
{
int a=1;
int b=2;
return a*b;
}
document.write(info());
{
int a=1;
int b=2;
return a*b;
}
document.write(info());
1
2
3
error
What are the three important manipulations done in a for loop on a loop variable?
Updation, Incrementation, Initialization
Initialization,Testing, Updation
Testing, Updation, Testing
Initialization,Testing, Incrementation
The unordered collection of properties, each of which has a name and a value is called _________
String
Object
Serialized Object
Array
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
What is the difference between the two lines given below ?
!!(obj1 && obj2);
(obj1 && obj2);
(obj1 && obj2);
Both the lines result in a boolean value True
Both the lines result in a boolean value False
Both the lines checks just for the existence of the object alone
The first line results in a real boolean value whereas the second line merely checks for the existence of the objects
What will be the shift() output of the following JavaScript code?
var a = [];
a.unshift(1);
a.unshift(22);
a.shift();
a.unshift(3,[4,5]);
a.shift();
a.shift();
a.shift();
a.unshift(1);
a.unshift(22);
a.shift();
a.unshift(3,[4,5]);
a.shift();
a.shift();
a.shift();
1
[4,5]
[3,4,5]
Exception is thrown
Consider the following code snippet :
var tensquared = (function(x) {return x*x;}(10));
Will the above code work ?
Yes, perfectly
Error
Exception will be thrown
Memory leak
Which of the operator is used to test if a particular property exists or not?
in
exist
within
exists
What will be the output of the following JavaScript code?
string a = hi;
string b =there;
alert(a+b);
string b =there;
alert(a+b);
hi
there
hithere
undefined
What are the three important manipulations done in a for loop on a loop variable?
Updation, Incrementation, Initialization
Initialization,Testing, Updation
Testing, Updation, Testing
Initialization,Testing, Incrementation
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
Consider the following code snippet :
var c = counter(), d = counter();
c.count()
d.count()
c.reset()
c.count()
d.count()
The state stored in d is :
c.count()
d.count()
c.reset()
c.count()
d.count()
1
0
Null
Undefined
Which is an equivalent code to invoke a function m of class o that expects two arguments x and y?
o(x,y);
o.m(x) && o.m(y);
m(x,y);
o.m(x,y);
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
In the following syntax, the data type within the square brackets must be ___________
book[datatype]=assignment_value;
An integer
A String
An object
Floating point
Consider the following code snippet.
for(var p in o)
console.log(o[p]);
The above code is equivalent to which code?
console.log(o[p]);
for (var i = 0;i < a.length;i++)
console.log(a[i]);
for (int i = 0;i < a.length;i++)
console.log(a[i]);
for (var i = 0;i <= a.length;i++)
console.log(a[i]);
for (var i = 1;i < a.length;i++)
console.log(a[i]);
What will be the output of the following JavaScript code?
7.25
-7.25
7
-7
What will be the output of the following JavaScript code?
var values=[1,2,3,4]
var ans=values.slice(1);
document.writeln(ans);
var ans=values.slice(1);
document.writeln(ans);
1, 2, 3, 4
2, 3, 4
1, 3, 4
error