What is a Conditional Statement in C#?

Conditional statements are a fundamental concept in programming that allows developers to control the flow of their code based on certain conditions. In C#, conditional statements are achieved through a variety of keywords and operators that allow you to check for certain conditions and execute specific blocks of code based on the results.

Conditional Statements in C Sharp

Conditional statements in C#

IF Statement in C#

If statement executes the block of code when the specified condition becomes true. If the given condition is not true or not satisfied, then that block will not execute.

Syntax

if(condition)
{
     // your code to execute 
}

Example

// Example of if condition

string name = "yogesh";
Console.WriteLine("Before IF Block");

if (name == "virat")
{
     Console.WriteLine("Name is virat");
}
if (name == "yogesh")
{
     Console.WriteLine("Name is Yogesh");
}
Console.WriteLine("After IF Block");

Output

IF Statement Output

Explanation

If Else Statement in C#

With the If statement, we can execute the block of code when the given condition becomes true. In this case, user will not understand what goes wrong. If we perform some operation or show the message to the user when the condition is satisfied but when it is not, then the user will not receive any message.

If Else statement can handle this kind of confusion. In the else block, we can define a code block that is executed when the condition is not satisfied.

Syntax

if(condition)
{
    // code block when condition satisfied 
}
else
{
   // code block when condition not satisfied 
}

Example

// Example of if else statement
string name = "virat";
Console.WriteLine("Before If Else Statement");

if (name == "yogesh")
{
     Console.WriteLine("Name is Yogesh");
}

else
{
     Console.WriteLine("Name is Not Yogesh");
}
Console.WriteLine("After If Else Statement");

Output

If Else Statement output.

Explanation

If Else If Statement in C#

If Else If is also called an If Else Ladder, which shows like a ladder with multiple legs. In this type of statement, we can define more than one condition and execute a block of code based on that condition.

In the If Else statement, we show that if the condition is not satisfied, then it will go into the else block. But what if we want to check other conditions? In this case, we can use If Else If statements.

Here you can define as many conditions as you want with different else if blocks. In this statement compiler first check the first condition if it is satisfied, then it will execute the code of that condition block else it will go to the next else if condition and do the same thing. If none of the defined conditions are satisfied, then it will execute the else block.

Here else, the block is not mandatory. You can define it if you want.

Syntax

If(condition)

{
     // code to execute when condition 1 satisfied 
}

else if(other condition)
{
     // code to execute when condition 2 satisfied 
}

else
{
    // code to execute when none of the above  satisfied 
}

Example 

// Example of if else if  statement
string name = "virat";
Console.WriteLine("Before If Else If Statement");

if (name == "yogesh")
{
     Console.WriteLine("Name is Yogesh");
}

else if (name == "virat")
{
     Console.WriteLine("Name is Virat");
}

else if (name == "rahul")
{
     Console.WriteLine("Name is Rahul");
}

else
{
     Console.WriteLine("Name is Undefine");
}
Console.WriteLine("After If Else If Statement");

Output

If Else If Ladder1

If Else If Ladder2

Explanation

Nested if Statement in C#

We can also define the conditional statement as another conditional statement. It is called Nested Condition. If we want to check other conditions when one of the condition is satisfied, then we can use this statement.

In the nested code block, we can add all types of conditional statements.

Syntax 

if(condition)
{
	if(nestedCondition)
	{

	}
	else
	{

	}

}

Example

// Example of Nested If statement

string name = "virat";
int age = 10;
Console.WriteLine("Before Nested If Statement");

if (name == "yogesh")
{
     if(age == 10)
     {
         Console.WriteLine("Age of Yogesh Is 10");
     }
     else if (age == 20)
     {
         Console.WriteLine("Age of Yogesh Is 20");
     }

}
else if (name == "virat")
{
     if (age == 10)
     {
         Console.WriteLine("Age of Virat Is 10");
     }
     else if (age == 20)
     {
         Console.WriteLine("Age of Virat Is 20");
     }
}
else
{
     Console.WriteLine("Name is Undefine");
}

Console.WriteLine("After Nested If Statement");

Output

Nested if statement output

Explanation

Switch Statement in C#

The switch statement is a control flow statement that allows a program to evaluate an expression and perform different actions based on the value of the expression. It provides an alternative to a series of if-else statements when multiple conditions need to be checked.

The switch statement takes an expression and compares it with a series of cases. Each case contains a value and a block of code to be executed if the expression matches that value. The value of the expression is compared against each case value in turn until a match is found. If a match is found, the corresponding block of code is executed, and the switch statement ends.

If no match is found, a default case can be specified to handle this situation. The default case is executed if none of the other case values match the expression. The default case is optional and can be omitted if no action is needed for the default scenario.

The switch statement provides a way to simplify code and make it easier to read and understand. It is often used to handle menu options, user input or to perform different actions based on the state of a program.

Syntax

switch(expression)

{
    case value1:
        // code block
        break;
    case value2:
        // code block
        break;
    // more cases
    default:
        // code block
        break;
}

The break statement is used inside a switch block to terminate the current case and move on to the next statement after the switch block.

If the break is not defined after a case, the code will continue to execute the next case until a break statement is encountered or the switch block ends. This is known as "falling through" the cases.

Falling through cases can sometimes be used intentionally to avoid duplicating code, but it can also lead to unexpected results if not handled carefully. In general, it's considered best practice to always include a break statement after each case unless you have a specific reason not to.

Example 

int dayOfWeek = 3;
string dayName;
switch (dayOfWeek)

{
     case 1:
         dayName = "Monday";
         break;
     case 2:
         dayName = "Tuesday";
         break;
     case 3:
         dayName = "Wednesday";
         break;
     case 4:
         dayName = "Thursday";
         break;
     case 5:
         dayName = "Friday";
         break;
     case 6:
         dayName = "Saturday";
         break;
     case 7:
         dayName = "Sunday";
         break;
     default:
         dayName = "Invalid day";
         break;
}

Console.WriteLine("Name Of Day Is: "+dayName);

Output

Switch Statement Output

Explanation

Nested Switch Statement in C#

A nested switch statement is a switch statement inside another switch statement. It is similar to a nested if-else statement, but it provides a more organized way of handling complex multiple conditions.

A nested switch statement is implemented by using one switch statement inside another switch statement. The inner switch statement can have its own set of cases, and the outer switch statement can have its own set of cases.

Example 

int outer = 1;
int inner = 2;
string message;

switch (outer)
{
case 1:
     switch (inner)
     {
         case 1:
             message = "Outer is 1 and Inner is 1";
             break;
         case 2:
             message = "Outer is 1 and Inner is 2";
             break;
         default:
             message = "Invalid Inner Value";
             break;
     }
     break;
case 2:
     message = "Outer is 2";
     break;
default:
     message = "Invalid Outer Value";
     break;
}

Console.WriteLine(message);

Output

Nested Switch Statement1

Nested Switch Statement2

Explanation

Summary

Conditional statements in C# allow developers to control the flow of their programs based on certain conditions. These statements provide a way to execute specific blocks of code based on whether certain conditions are true or false, making it an essential tool for programming.