1. The if Statement
Use the if statement to specify a block of C# code to be executed if a condition is True.

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

Example
   int x = 20;
   int y = 18;
   if (x > y) 
   {
      Console.WriteLine("x is greater than y");
   }

2. The else Statement
Use the else statement to specify a block of code to be executed if the condition is False.
Syntax
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 time = 20;
   if (time < 18) 
   {
      Console.WriteLine("Good day.");
   } 
   else 
   {
      Console.WriteLine("Good evening.");
   }
// Outputs "Good evening

3.The else if Statement
Use the else if statement to specify a new condition if the first condition is False.

Syntax
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 time = 22;
    if (time < 10) 
    {
       Console.WriteLine("Good morning.");
    } 
    else if (time < 20) 
    {
       Console.WriteLine("Good day.");
    } 
    else 
    {
        Console.WriteLine("Good evening.");
    }
// Outputs "Good evening."

4.C# Switch Statements
Use the switch statement to select one of many code blocks to be executed.

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

5.C# For Loop
When you know exactly how many times you want to loop through a block of code, use the for loop instead of a while loop:

Syntax
for (statement 1; statement 2; statement 3) 
{
    // code block to be executed
}
Statement 1 is executed (one time) before the execution of the code block.
Statement 2 defines the condition for executing the code block.
Statement 3 is executed (every time) after the code block has been executed.
The example below will print the numbers 0 to 4:

Example
for (int i = 0; i < 5; i++) 
{
    Console.WriteLine(i);
}

6.C# Break and Continue
C# Break
You have already seen the break statement used in an earlier chapter of this tutorial. It was used to "jump out" of a switch statement.

The break statement can also be used to jump out of a loop.
This example jumps out of the loop when i is equal to 4:

Example 
for (int i = 0; i < 10; i++) 
{
   if (i == 4) 
   {
     break;
   }
   Console.WriteLine(i);
}

7.C# Continue
The continue statement breaks one iteration (in the loop), if a specified condition occurs, and continues with the next iteration in the loop.

This example skips the value of 4:
Example
for (int i = 0; i < 10; i++) 
{
   if (i == 4) 
   {
      continue;
   }
      Console.WriteLine(i);
}