TypeScript Logical Operators

Logical operators are used in TypeScript to combine conditions or invert a condition's value. These operators are often used in decision-making and control flow.

Types of Logical Operators

• AND (&&)
• OR (||)
• NOT (!)

AND (&&) Operator

The && operator (Logical AND) checks if both conditions are true. If they are, it returns true. If either condition is false, it returns false.

Syntax:

condition1 && condition2

Example:

let age = 25;
let hasDrivingLicense = true;
 
if (age > 18 && hasDrivingLicense) {
  console.log("You can drive.");
} else {
  console.log("You cannot drive.");
}

Output:

You can drive.

OR (||) Operator

The || operator (Logical OR) checks if at least one of the conditions is true. If either condition is true, it returns true. If both conditions are false, it returns false.

Syntax:

condition1 || condition2

Example:

let isWeekend = true;
let isHoliday = false;
 
if (isWeekend || isHoliday) {
  console.log("You can relax today.");
} else {
  console.log("You need to work today.");
}

Output:

You can relax today.

NOT (!) Operator

The ! operator (Logical NOT) inverts the value of a condition. If the condition is true, it returns false, and if the condition is false, it returns true.

Syntax:

!condition

Example:

let isRaining = false;
 
if (!isRaining) {
  console.log("You can go outside without an umbrella.");
} else {
  console.log("You need an umbrella.");
}

Output:

You can go outside without an umbrella.

Combining Logical Operators

You can combine multiple logical operators to create complex conditions.

Example:

let age = 20;
let hasID = true;
let isMember = false;
 
if ((age >= 18 && hasID) || isMember) {
  console.log("You can enter the club.");
} else {
  console.log("You cannot enter the club.");
}

Output:

You can enter the club.

Conclusion

Logical operators in TypeScript make it easy to work with multiple conditions. By understanding how &&, ||, and ! work, you can control the flow of your programs effectively.