C# For Loop
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 explained
Statement 1 sets a variable before the loop starts (int i = 0
).
Statement 2 defines the condition for the loop to run (i
must be less than
5
). If the condition is true
, the loop will start over again, if it is false
,
the loop will end.
Statement 3 increases a value (i++
) each time the code block in the loop has
been executed.
Another Example
This example will only print even values between 0 and 10:
Nested Loops
It is also possible to place a loop inside another loop. This is called a nested loop.
The "inner loop" will be executed one time for each iteration of the "outer loop":
Example
// Outer loop
for (int i = 1; i <= 2; ++i)
{
Console.WriteLine("Outer: " + i); // Executes 2 times
// Inner loop
for (int j = 1; j <= 3; j++)
{
Console.WriteLine(" Inner: " + j); // Executes 6 times (2 * 3)
}
}