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
Correct Answer :
B. A String
Explanation: The value inside the square bracket is used to access that data element or the property of the object. When using square bracket notation, the expression inside the square brackets must evaluate to a string or a value that can be converted to a string.
Related Questions
Which of the operator is used to test if a particular property exists or not?
in
exist
within
exists
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 will be the possible output of the following JavaScript code?
var a = [1,2,3,4,5];
a.slice(0,3);
a.slice(0,3);
Returns [1,2,3]
Returns [4,5]
Returns [1,2,3,4]
Returns [1,2,3,4,5]
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
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 add=new Function(num1,num2,return num1+num2);
document.writeln(add(2,5));
document.writeln(add(2,5));
2
5
Error
7
What will be the output of the following JavaScript code?
int sum=0;
var arr = [10,15,20,30];
arr.forEach(function myFunction(element)
{
sum= sum+element;
});
document.writeln(sum);
var arr = [10,15,20,30];
arr.forEach(function myFunction(element)
{
sum= sum+element;
});
document.writeln(sum);
70
75
10
error
The method or operator used to identify the array is __________
isarrayType()
==
===
typeof
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
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
What will be the output of the following JavaScript code?
var grade='B';
var result;
switch(grade)
{
case 'A':
{
result+=10;
break;
}
case 'B':
{
result+= 9;
break;
}
case 'C':
{
result+= 8;
break;
}
default:
result+= 0;
}
document.write(result);
var result;
switch(grade)
{
case 'A':
{
result+=10;
break;
}
case 'B':
{
result+= 9;
break;
}
case 'C':
{
result+= 8;
break;
}
default:
result+= 0;
}
document.write(result);
10
9
8
0
The statement a===b refers to _________
Both a and b are equal in value, type and reference address
Both a and b are equal in value
Both a and b are equal in value and type
There is no such statement
The main purpose of a Live Wire in NetScape is to ________
Create linkage between client side and server side
Permit server side, JavaScript code, to connect to RDBMS
Support only non relational database
To interpret JavaScript code
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
What kind of expression is new Point(2,3)?
Primary Expression
Object Creation Expression
Invocation Expression
Constructor Calling Expression
What will be the output of the following JavaScript code?
125
25
5
Error
Among the keywords below, which one is not a statement?
debugger
with
if
use strict
Consider the following code snippet :
var grand_Total=eval(10*10+5);
The output for the above statement would be :
10*10+5
105 as a string
105 as an integer value
Exception is thrown
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 escape sequence stands for _________
Floating numbers
Representation of functions that returns a value
is not present in JavaScript
Form feed
What will be the output of the following JavaScript code?
var arr=[1,2,3];
var rev=arr.reverse();
document.writeln(rev);
var rev=arr.reverse();
document.writeln(rev);
1, 2, 3
3, 2, 1
3
1
One of the special feature of an interpreter in reference with the for loop is that ___________
Before each iteration, the interpreter evaluates the variable expression and assigns the name of the property
The iterations can be infinite when an interpreter is used
The body of the loop is executed only once
the iteration is finite when an interpreter is used
What will be the output of the following Javascript code?
<script>
txt1 = “ one”;
txt1 += “two”;
document.getElementById("demo").innerHTML = txt1;
</script>
txt1 = “ one”;
txt1 += “two”;
document.getElementById("demo").innerHTML = txt1;
</script>
onetwo
one two
error
undefined
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
The reduce and reduceRight methods follow a common operation called __________
filter and fold
inject and fold
finger and fold
fold
When does the function name become optional in JavaScript?
When the function is defined as a looping statement
When the function is defined as expressions
When the function is predefined
when the function is called
The expression of calling (or executing) a function or method in JavaScript is called ________
Primary expression
Functional expression
Invocation expression
Property Access Expression
JavaScript _________ when there is an indefinite or an infinite value during an arithmetic computation.
Prints an exception error
Prints an overflow error
Displays Infinity
Prints the value as such
Consider the following code snippet.
while (a != 0)
{
if (a == 1)
continue;
else
a++;
}
What will be the role of the continue keyword in the above code snippet?
{
if (a == 1)
continue;
else
a++;
}
The continue keyword restarts the loop
The continue keyword skips the next iteration
The continue keyword skips the rest of the statements in that iteration
The continue keyword breaks out of the loop
What will be the output of the following JavaScript code?
function compare()
{
int num=2;
char b=2;
if(a==b)
return true;
else
return false;
}
{
int num=2;
char b=2;
if(a==b)
return true;
else
return false;
}
true
false
runtime error
compilation error