Conditional Statements | Control Structures

Introduction

Conditional statements are used to perform different actions based on different conditions. In C#, we have several types of conditional statements, including if, else, else if, switch, and ternary operator.

If Statement

The if statement is used to execute a block of code only if a specified condition is true.

if (condition) {
// block of code to be executed if the condition is true
}

Example:

int number = 10;
if (number > 5) {
Console.WriteLine("Number is greater than 5");
}

Output:
Number is greater than 5

If...Else Statement

The if...else statement is used to execute one block of code if a condition is true and another block of code if the condition is false.

if (condition) {
// block of code to be executed if the condition is true
} else {
// block of code to be executed if the condition is false
}

Example:

int number = 3;
if (number > 5) {
Console.WriteLine("Number is greater than 5");
} else {
Console.WriteLine("Number is not greater than 5");
}

Output:
Number is not greater than 5

If...Else If...Else Statement

The if...else if...else statement is used to specify a new condition to test if the first condition is false.

if (condition1) {
    // block of code to be executed if condition1 is true
} else if (condition2) {
    // block of code to be executed if the condition1 is false and condition2 is true
} else {
    // block of code to be executed if the condition1 is false and condition2 is false
}

Example:

int number = 7;
if (number > 10) {
    Console.WriteLine("Number is greater than 10");
} else if (number > 5) {
    Console.WriteLine("Number is greater than 5 but less than or equal to 10");
} else {
    Console.WriteLine("Number is 5 or less");
}

Output:
Number is greater than 5 but less than or equal to 10

Switch Statement

The switch statement selects one of many code blocks to be executed.

switch(expression) {
    case x:
        // code block
        break;
    case y:
        // code block
        break;
    default:
        // code block
}

Example:

int day = 3;
switch (day) {
    case 1:
        Console.WriteLine("Monday");
        break;
    case 2:
        Console.WriteLine("Tuesday");
        break;
    case 3:
        Console.WriteLine("Wednesday");
        break;
    default:
        Console.WriteLine("Other day");
}

Output:
Wednesday

Ternary Operator

The ternary operator is a shorthand for the if...else statement.

variable = (condition) ? expressionTrue : expressionFalse;

Example:

int number = 8;
string result = (number > 5) ? "Greater than 5" : "5 or less";
Console.WriteLine(result);

Output:
Greater than 5

Conditional Statements in C#

Introduction

If Statement

If...Else Statement

If...Else If...Else Statement

Switch Statement

Ternary Operator