An expression is a special kind of statement that evaluates to a value. Every expression consists of
- Operands: Represents the data.
- Operator: which performs certain operations on operands.
Consider the following expression – 2 / 3, in the expression, 2 and 3 are operands and the symbol /is the operator.
JavaScript supports the following types of operators:
- Arithmetic Operators
- Relational Operators
- Logical Operators
- Bitwise Operators
- Assignment Operators
- Type Operators
- Miscellaneous Operators
Arithmetic Operators: As we know these are the basic mathematical operators available in JavaScript ES6.
| Operator | Function |
|---|---|
| Addition(+) | Returns sum of the operands. |
| Subtraction(-) | Returns the difference of the values. |
| Multiplication(*) | Returns the product of the values. |
| Division(/) | Performs division and returns the quotient. |
| Modulus(%) | Performs division and returns the remainder. |
| Increment(++) | Increases the value of the variable by one. |
| Decrement(- -) | Decreases the value of the variable by one. |
Example:
javascript
<script> var num1 = 10.5 var num2 = 2.5 document.write("Sum : " + (num1 + num2) + "<br>"); document.write("Difference : " + (num1 - num2) + "<br>") document.write("Product : " + num1 * num2 + "<br>") document.write("Quotient : " + num1 / num2 + "<br>") document.write("Remainder : " + num1 % num2 + "<br>") // pre-increment document.write("Value of num1 after pre-increment : " + (++num1) + "<br>") // post-increment document.write("Value of num1 after post-increment : " + (num1++) + "<br>") // pre-decrement document.write("Value of num2 after pre-decrement : " + (--num2) + "<br>") // post-decrement document.write("Value of num2 after post-decrement : " + (num2--) + "<br>")</script> |
Output:
Sum : 13 Difference : 8 Product : 26.25 Quotient : 4.2 Remainder : 0.5 Value of num1 after pre-increment : 11.5 Value of num1 after post-increment : 11.5 Value of num2 after pre-decrement : 1.5 Value of num2 after post-decrement : 1.5
Relational Operators: An operator that compares two values. Relational operators are sometimes called comparison operators.
| Operator | Function |
|---|---|
| > | Returns true if the left operand is greater than right else, false. |
| < | Returns true if the left operand is lesser than right else, false. |
| >= | Returns true if the left operand is greater than or equal to right else, false. |
| <= | Returns true if the left operand is lesser than or equal to right else, false. |
| == | Returns true if both the operands are same else, false./td> |
| == | Returns true if both the operands are the same else, false. |
| != | Returns true if both the operands are not same else, false. |
Example:
javascript
<script> document.write("11>12 : " + (11 > 12) + "<br>"); document.write("11<12 : " + (11 < 12) + "<br>") document.write("12>=11 : " + (12 >= 11) + "<br>") document.write("12<=12 : " + (12 <= 12) + "<br>") document.write("11==11 : " + (11 == 11) + "<br>") document.write("11!=11 : " + (11 != 11) + "<br>")</script> |
Output:
11>12 : false 11=11 : true 12<=12 : true 11==11 : true 11!=11 : false
Logical Operators: Logical operators are used to combine two or more relational statements.
| Operator | Function |
|---|---|
| And(&&) | Return true if all the relational statements combined with && are true, else false. |
| Or(||) | Return true if at least one of the relational statements combined with || is true, else false.< |
| Not(!) | Returns the inverse of the relational statement’s result. |
Example:
javascript
<script> // Returns true as every statement is true. document.write("13>12 && 12>11 && 9==9 : " + (13 > 12 && 12 > 11 && 9 == 9) + "<br>"); // Returns false as 11>12 is false. document.write("11>12 && 12>11 && 9==9 : " + (11 > 12 && 12 > 11 && 9 == 9) + "<br>") // As one true statement is enough to return. document.write("11>12 || 12>11 || 9==9 : " + (11 > 12 || 12 > 11 || 9 == 9) + "<br>") // Returns false as 11>12 is not true. document.write("11>12 && (12>11 || 9==9) : " + (11 > 12 && (12 > 11 || 9 == 9)) + "<br>")</script> |
Output:
13>12 && 12>11 && 9==9 : true 11>12 && 12>11 && 9==9 : false 11>12 || 12>11 || 9==9 : true 11>12 && (12>11 || 9==9) : false
Bitwise Operators: A bitwise operator is an operator used to perform bitwise operations on bit patterns or binary numerals that involve the manipulation of individual bits.
| Operator | Function |
|---|---|
| Bitwise AND(&) | Compares each bit of the first operand to the corresponding bit of the second operand. If both bits are 0, the corresponding result bit is set to 0, else 1. |
| Bitwise OR(|) | Compares each bit of the first operand to the corresponding bit of the second operand. If both bits are 1, the corresponding result bit is set to 1, else 0. |
| Bitwise XOR(^) | Inverts the bits of its corresponding operand |
| Left shift(<<) | Will shift the ‘n’ number of bits to the left side, and n bits with the value 0 will be filled on the right side. Example: x=2, t=4, x<<t, for easy evaluation it performs  . |
| Right shift(>>) | Will shift the ‘n’ number of bits to the right side, and ‘n’ bits with the value 0 will be filled on the left side. Example: x=2, t=4, x>>t, for easy evaluation it performs  . |
| Zero-fill right shift | Shifts a in binary representation b (< 32) bits to the right, discarding bits shifted off, and shifting in zeroes from the left |
Example:
javascript
<script> document.write("2&3 : " + (2 & 3) + "<br>"); document.write("2|3 : " + (2 | 3) + "<br>"); document.write("2^3 : " + (2 ^ 3) + "<br>"); document.write("~4 : " + (~4) + "<br>"); document.write("2<<3 : " + (2 << 3) + "<br>"); document.write("2>>3 : " + (2 >> 3) + "<br>");</script> |
Output:
2&3 : 2 2|3 : 3 2^3 : 1 ~4 : -5 2<>3 : 0
Assignment Operators: An assignment operator is the operator used to assign a new value to the variable, property, event or indexer element.
| Operator | Function |
|---|---|
| Simple Assignment(=) | Assigns the value of the right operand to left operand. |
| Add and Assignment(+=) | It adds the right operand to the left operand and assigns the result to the left operand. |
| Subtract and Assignment(-=) | It subtracts the right operand from the left operand and assigns the result to the left operand. |
| Multiply and Assignment(*=) | It multiplies the right operand with the left operand and assigns the result to the left operand. |
| Divide and Assignment(/=) | It divides the left operand with the right operand and assigns the result to the left operand. |
Example:
javascript
<script> var a = 12; var b = 10; a = b; document.write("a = b : " + a + "<br>"); a += b; document.write("a += b : " + a + "<br>") a -= b; document.write("a -= b : " + a + "<br>") a *= b; document.write("a *= b : " + a + "<br>") a /= b; document.write("a /= b : " + a + "<br>")</script> |
Output:
a = b : 10 a += b : 20 a -= b : 10 a *= b : 100 a /= b : 10
Type Operators: It is a unary operator. This operator returns the data type of the operand.
Syntax:
typeof(operand)
Example:
javascript
<script> var a = 12; var b = "Geeks"; var b = "Geeks"; var c = true; var d = String; document.write("a is " + typeof(a) + "<br>"); document.write("b is " + typeof(b) + "<br>") document.write("c is : " + typeof(c) + "<br>") document.write("d is : " + typeof(d) + "<br>")</script> |
Output:
a is number b is string c is : boolean d is : function
Miscellaneous Operators:These are the operators that, does different operators when used at different types of occasions.
| Operator | Function |
|---|---|
| Negation operator (-) | Changes the sign of a value. |
| Concatenation operator (+) | +, when applied to strings it appends them. |
| Conditional Operator (?) | It can use as a ternary operator. |
Example:
javascript
<script> var a = "neveropen=>"; var b = "A Computer science portal."; var c = true; var d = 9; // Concatenation document.write("a+b : " + a + b + "<br>"); // Ternary Operator var c = 2 > 3 ? "yes is 2>3" : "No, It is not." document.write("2>3 :" + c + "<br>") // Negation d = -d; document.write("d = -d : " + d + "<br>")</script> |
Output:
a+b : neveropen=>A Computer science portal. 2>3 :No, It is not. d = -d : -9
