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# JavaScript comparison and logical operators

Comparison and logical operators for testing true or false.

## Comparison

In comparison logic statements used to measure variables or values ​​are equal.

x = 5, the table below explains the comparison operators:

Operators description Compare return value Examples
== equal x == 8 false Examples >>
x == 5 true Examples >>
=== Absolutely equal to (value and type are equal) x === "5" false Examples >>
x === 5 true Examples >>
! = not equal to x! = 8 true Examples >>
! == Absolutely not equal to (or type a value not equal) x! == "5" true Examples >>
x! == 5 false Examples >>
> more than the x> 8 false Examples >>
< Less than x <8 true Examples >>
> = greater than or equal to x> = 8 false Examples >>
<= less than or equal to x <= 8 true Examples >>

## how to use

You can use comparison operators in conditional statements to compare values, and then to take action based on the results:

if (age<18) x="Too young";

## Logical Operators

Logical operators used to determine the logic between variables or values.

Given x = 6 and y = 3, the table below explains the logical operators:

&& and (x < 10 && y > 1) 为 true
|| or (x==5 || y==5) 为 false
! not !(x==y) 为 true

## Conditional operator

JavaScript also contains certain conditions based on the variable conditions of the assignment operator.

### grammar

variablename =( condition )? value1 : value2

## Examples

If the variable age is less than 18, then assigned to the variable voteable "too young", otherwise assign "Age has been reached."

voteable=(age<18)?"年龄太小":"年龄已达到";
try it"