In this post, we will be learning about JavaScript's comparison operators.
Comparisons Operators
Comparison operators are used for determining whether a literal equal or differs from another literal.
Two equal signs ("==") will check only the value of literals, while three equal signs ("===") checks whether they are both the same value and the same type. For example, if x equals 6, then the operators below will return the value listed in the return column.
Operator | Description | Comparing | Returns | ||
"==" | equals to | x == 9 | false | ||
x == 6 | true | ||||
x == "6" | true | ||||
"===" | equals to | x === 9 | false | ||
x == 6 | true | ||||
x == "6" | false |
Of particular note is that for two equal signs, 6 and "6"(a string) are equal, while for three equal signs they are not.
How Comparison Operators Can be Used
Comparisons are used to determine whether a variable matches a certain condition.
If the condition matches (the condition is true), we execute some block of code. Otherwise, (the condition is false), we execute another block of code.
JavaScript Code
if(age<18)
{
document.write("Sorry, you are too young");
}
else
{
document.write("Congratulation, you are old enough!");
}
Logical Operator
We use logical operators to specify relations between conditions.
For example, we can see whether a variable meets condition A and condition B or we can see whether a variable meets condition A or condition B.
Operator | Description | Comparing | ||||||
"==" | and | (x < 10 && y > 1) is true | ||||||
" | " | or | (x == 5 | y == 5) is false | ||||
"!" | not | (x != y) is true |
Comparing Different Types
Case | Value |
2 < 12 | true |
2 < "12" | false |
2 < "John" | false |
2 > "John" | false |
2 == "John" | false |
"2" < "12" | false |
"2" > "12" | true |
"2" == "12" | false |
The above are some examples of types being compared.