Toán tử trong javascript - Version đầy đủ

javascript,operator

javascript and operator

//AND Operator expressed as &&

const x = 7;
const y = 4;

(x == 7 && y == 5); // false
(x == 3 && y == 4); // false
(x == 7 && y == 4); // true

if (condition == value && condition == otherValue) {
  return something;
}

or operator in javascript

//The OR operator in Javascript is 2 verticals lines: ||

var a = true;
var b = false;

if(a || b) {
    //one of them is true, code inside this block will be executed
}

javascript and

var hungry=true;
var slow=true;
var anxious=true;

//&& means and
if(hungry && slow && anxious){ 
    var cause="weed";
}

or statment javscript

if (x === 5 || x === 8)
  console.log("x is eaqual to 5 OR 8")

or operator javascript

var a = 2;
var b = 5;
var c = 10;

if (a === 3 || a === 2) {
    console.log("TRUE");
} else {console.log("FALSE");}
if (a === 4 || b === 3 || c === 11) {
    console.log("TRUE");
} else {console.log("FALSE");}
if (b === 5 || c != 10) {
    console.log("TRUE");
} else {console.log("FALSE");}

/* Output:
TRUE
FALSE
TRUE
*/

eaqual signs in javascript

//x = 5

operator  |    example     |    output  |    explination

==            x == 8        false        equal to
            x == 5        true
            x == "5"    true

===            x === 5        true        equal value and type
            x === "5"    false

!=            x != 8        true        not equal

!==            x !== 5        false        not equal value or not equal type
            x !== "5"    true
            x !== 8        true

>            x > 8        false        greater than

<            x < 8        true        less than

>=            x >= 8        false        greater than or equal to

<=            x <= 8        true        less than or equal to

less than equal to in javascript

| <= | less than or equal to |    x <= 8 | true |

=== javascript

// ===    means equal value and equal type
var x = 5

// true
x === 5

// false
x === "5"

and operator in javascript

//&& returns true if both values are true
//or returns the second argument if the first is true
var a = true
var b = ""
var c = 1

true && "" //""
"" && 1 //""
false && 5 //false

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