# if-then-(else)

if-then construct is the most common conditional statement. It looks like this,

if (boolean expression)
{
  // if boolean expression evaluates to True
}

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If the condition is true then the body of the if statement is run.

You can also use else.

if (boolean expression)
{
  // if boolean expression evaluates to True
}
else
{
  // if boolean expression evaluates to False
}

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If the condition is false then the body of the else statement is run. Using else is optional.

# 👍 Best Practice

Always enclose if and else body in braces {}

if (num < 10)
{
  Console.WriteLine($"{num} is less than 10");
}
else
{
  Console.WriteLine($"{num} is greater than 10");
}

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WARNING

The following style of code is bad. Do not use it.

If your if or else body has a single line then you can remove the enclosing braces {}.

if (num < 10)
  Console.WriteLine($"{num} is less than 10");
else
  Console.WriteLine($"{num} is greater than 10");

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But never write a if and else body without braces.