Check if a Variable is equal to True in JavaScript

Check if a Variable is equal to True #

Use the strict equality (===) operator to check if a variable is equal to true - myVar === true. The strict equality operator will return true if the variable is equal to true, otherwise it will return false.

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const myVar = true;

if (myVar === true) {
  console.log('✅ myVar is equal to true');
} else {
  console.log('⛔️ myVar is not equal to true');
}

We used the strict equality (===) operator to check if the value, stored in the myVar variable is equal to true.

The operator returns a boolean result:

• true if the values are equal
• false if the values are not equal

The strict equality (===) operator considers two values of different types to be different, as opposed to the loose equality (==) operator.

This means that if we compare true with any other type, the strict equality operator (===) would return false.

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console.log(true === true); // 👉️ true
console.log(true === 'true'); // 👉️ false
console.log(true === 1); // 👉️ false

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const myVar = true;

if (myVar) {
  console.log(`🚨 a is NOT
       false, 0, empty string, null, undefined, NaN`);
} else {
  console.log(`⛔️️ a is ONE OF
       false, 0, empty string, null, undefined, NaN`);
}

The if statement checks if the myVar variable is truthy. Truthy are all values that are not falsy.

The falsy values in JavaScript are: false, 0, "", null, undefined, NaN.

This means that, for our if block to run the value stored in the myVar variable can be anything other than the 6 falsy values, it doesn't have to be necessarily equal to true.

Things can go wrong when you use this approach to check if a variable is equal to true. Here's an example.

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const myVar = [];

if (myVar) {
  console.log('✅ this runs');
} else {
  console.log("⛔️ this doesn't run");
}

Because the empty array is considered a truthy value, the if block runs.

When checking if a variable is equal to a specific value, it's always good to be explicit.

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const myVar = [];

if (myVar === true) {
  console.log("⛔️ this doesn't run");
} else {
  console.log('✅ this runs');
}

Further Reading #

• How to Check if a Value is Falsy in JavaScript
• How to Check if a Variable is False in JavaScript