Conditional logic in C#

What is conditional logic?

Conditional logic is a way of thinking that allows you to make decisions or draw conclusions based on given conditions or premises. It is a fundamental aspect of critical thinking and problem-solving that is used in many different fields and situations.

Here is a real-life example of conditional logic:

You are planning a vacation and want to choose the best destination. You create a list of criteria that the destination should meet, such as good weather, affordable prices, and interesting attractions. You then research different destinations and determine which ones meet the criteria you have set. The destinations that meet all of the criteria are the ones that you consider as potential vacation spots.

In this example, the criteria (the conditions) are used to evaluate and compare the different destinations, and the conclusion (the decision) is based on which destinations meet the criteria.

Why need conditional logic?

Conditional logic is a fundamental building block of programming, and it is used in almost all programs to some degree. It allows you to specify different blocks of code to be executed based on certain conditions, which is essential for writing programs that can adapt to different inputs and handle various scenarios.

Here are a few examples of why conditional logic is important:

• Conditional logic allows you to check the validity of user input. For example, if you are writing a program that asks the user to enter their age, you might want to check that the user has entered a valid age (e.g., a positive integer) before proceeding.
• It allows you to handle different cases or scenarios in your program. For example, if you are writing a program that processes a list of numbers, you might want to handle the case where the list is empty differently from the case where it is not.
• It allows you to make decisions in your program based on certain conditions. For example, if you are writing a program that calculates the cost of an order, you might want to offer a discount to certain customers based on their purchase history or membership status.

Overall, conditional logic is an essential tool for writing programs that can adapt to different inputs and handle various scenarios.

Conditional logic in C#

Conditional logic in C# is a programming construct that allows developers to specify different blocks of code to be executed depending on certain conditions. It is a way of controlling the flow of a program based on certain criteria being met. Conditional logic is implemented using various control structures in C#, such as the if statement, else statement, else if statement, nested if statements, switch statement, and ternary operator.

"if" statement

One way to implement conditional logic in C# is with the if statement. The if statement allows you to execute a block of code if a certain condition is true. Here is an example of an if statement in C#:

int x = 5;

if (x > 10)
{
    Console.WriteLine("x is greater than 10");
}

In this example, the if statement checks to see if the value of x is greater than 10. Since it is not, the code block inside the if statement is not executed.

"else" statement

You can also use the else statement in conjunction with the if statement to execute a different block of code if the condition in the if statement is not true. Here is an example of using the else statement:

int x = 5;

if (x > 10)
{
    Console.WriteLine("x is greater than 10");
}
else
{
    Console.WriteLine("x is not greater than 10");
}

In this example, the code block inside the else statement is executed because the condition in the if statement is not true.

"else if" statement

You can also use the else if statement to specify additional conditions to check. Here is an example of using the "else if" statement:

int x = 5;

if (x > 10)
{
    Console.WriteLine("x is greater than 10");
}
else if (x == 10)
{
    Console.WriteLine("x is equal to 10");
}
else
{
    Console.WriteLine("x is less than 10");
}

In this example, the code block inside the else if statement is not executed because the condition in the if statement is not true, but the code block inside the else statement is executed because the condition in the else if statement is not true.

nested "if" statement

You can also use nested if statements to specify even more complex conditions. Here is an example of using nested if statements:

int x = 5;
int y = 10;

if (x > 10)
{
    if (y > 10)
    {
        Console.WriteLine("x and y are both greater than 10");
    }
    else
    {
        Console.WriteLine("x is greater than 10 and y is not");
    }
}
else
{
    Console.WriteLine("x is not greater than 10");
}

In this example, the code block inside the outer if statement is not executed because the condition in the if statement is not true.

"switch" statement

Another way to implement conditional logic in C# is with the switch statement. The switch statement allows you to execute a block of code based on the value of a certain expression. Here is an example of a switch statement in C#:

int x = 5;

switch (x)
{
    case 1:
        Console.WriteLine("x is 1");
        break;
    case 5:
        Console.WriteLine("x is 5");
        break;
    case 10:
        Console.WriteLine("x is 10");
        break;
    default:
        Console.WriteLine("x is not 1, 5, or 10");
        break;
}

In this example, the code block inside the `case 5:` statement is executed because the value of `x` is 5. The `break` statement is used to exit the `switch` statement once a match is found.

Ternary Operator "?:"

Finally, C# also offers the ternary operator, which allows you to specify a conditional expression in a concise way. The ternary operator has the following syntax:

(condition) ? (true expression) : (false expression)

Here is an example of using the ternary operator:

int x = 5;
int y = (x > 10) ? 100 : 200;
Console.WriteLine(y); // Outputs 200

In this example, the value of `y` is assigned the value of 200 because the condition `x > 10` is not true.

In conclusion, C# offers various ways to implement conditional logic in your programs, including the `if` statement, `else` statement, `else if` statement, nested `if` statements, `switch` statement, and ternary operator. Understanding how to use these tools effectively is essential for writing efficient and effective C# programs.