6 Types of operators in JavaScript summary

The JavaScript operators mainly include:

1. Arithmetic operators
2. Assignment operators
3. Comparison operators
4. Ternary operators
5. logical operators
6. String Join operators

operator	Description	Example	result of Operation
+	Add	y = 2+1	y = 3
-	Reducing	y = 2-1	y = 1
*	By	y = 2*3	y = 6
/	In addition, returns the result as a floating-point type	y = 6/3	y = 2
%	Remainder, returns the result as a floating-point type Requires both operands to be integers	y = 6%4	y = 2
++	Sliding scale, divided into pre-plus and post-plus The Boolean value and NULL will not be valid	y = 2 ++y (ex Plus) y++ (rear add)	y = 3
--	Descending, divided into former descending and after diminishing The Boolean value and NULL will not be valid	y = 2 --y (pre-minus) y--(post-subtraction)	y = 1

For the pre-plus and post-add, the result of the execution is the variable plus 1, the difference is that the execution of the return results are not the same, refer to the following two examples:

var x = 2;alert (++x); Output: 3alert (x); Output: 3var y = 2;alert (y++); Output: 2alert (y); Output: 3

Diminishing the same.

Assignment operators

Assignment operator = for assignment operations, the function of the assignment operator is to assign the right value to the left variable. Set y = 6, see the following table:

operator	Example	equivalent to	result of Operation
=	y = 6	?	y = 6
+=	Y + = 1	y = y+1	y = 7
-=	Y-= 1	y = y-1	y = 5
*=	Y *= 2	y = y*2	y = 12
/=	Y/= 2	y = Y/2	y = 3
%=	Y%= 4	y = y%4	y = 2

Assignment Operations Nesting use

Assignment operators can be nested using:

y = (x = 2) + 5;    Results: x=2,y=7

Comparison operators

operator	Description	Example	result of Operation
==	Equals	2 = = 3	FALSE
===	Constant Equals (the value and type are to be compared)	2 = = = 2 2 = = = "2"	TRUE FALSE
!=	Not equal to, can also write <>	2 = = 3	TRUE
>	Greater than	2 > 3	FALSE
<	Less than	2 < 3	TRUE
>=	Greater than or equal	2 >= 3	FALSE
<=	Less than or equal	2 <= 3	TRUE

Comparison operators can also be used for string comparisons.

Ternary operators

Ternary can be seen as a special comparison operator:

(EXPR1)? (EXPR2): (EXPR3)

Syntax Explanation: When EXPR1 evaluates to TRUE, the value of the entire expression is expr2, otherwise EXPR3.

Example:

x = 2;y = (x = = 2)? X:1;alert (y); Output: 2

This example determines whether the value of X equals 2, and if X equals 2, then the value of y equals X (that is, 2), whereas Y equals 1.

Tips

In order to avoid errors, it is a good idea to enclose the three-operator expressions in parentheses.

logical operators

operator	Description	Example	result of Operation
&&	Logic and (and)	x = 2; y = 6; X && y > 5	FALSE
||	Logical OR (OR)	x = 2; y = 6; X && y > 5	TRUE
!	Logic is not, take the opposite side of logic	x = 2; y = 6; ! (x > Y)	TRUE

String Join operators

The Join operator + is primarily used to concatenate two strings or string variables. Therefore, when you use the operator for a string or string variable, you do not do an addition calculation on them.

Example:

x = "Beijing"; y = x + "Hello!" "; Result: y = "Beijing Hello!" "//To add a space between two strings, insert a space into a string: y = x +" Hello! "; Result: y = "Beijing Hello!" "

When you do a join (add) operation on strings and numbers, the numbers are first converted to strings and then concatenated (summed):

x = 25;y = "I am this year" + x + "year old"; Result: y = "I am 25 years old"

6 Types of operators in JavaScript summary