If statement

An if statement is a conditional statement in programming that, if true, performs a specified function or displays information on the screen. Below is a general example of an if statement, not specific to any particular programming language.

if (X < 10) {
  print "Hello John";
}

In the example above, if the value of X equals any number less than 10, the program displays "Hello John" when the script is run.

Examples of if statements

Below are examples of the same if statement above using other programming languages, including C++, Java, JavaScript, Perl, PHP (PHP: Hypertext Preprocessor), Python, Ruby, and Visual Basic.

C#

if (X < 10)
{
  Console.WriteLine("Hello John.");
}

C++

if (X > 10) {
  std::cout << "Hello John." << std::endl;
}

Java

if (X < 10) {
  System.out.println("Hello John.");
}

JavaScript & HTML

<p id="example">Display Javascript output here</p>
if (X < 10) {
  document.getElementById("example").innerHTML = "Hello John.";
}

Perl

if ($X < 10) {
  print "Hello John.";
}

PHP

if ($X < 10) {
  echo "Hello John.";
}

Python

if X < 0:
  print("Hello John.")

Ruby

if X < 10
  puts "Hello John."
end

Visual Basic

If X < 10 Then
  message = "Hello John."
Console.WriteLine(message)

Conditional expression, Else, Elseif, Exists, If else, Logical decision, Programming terms, Statement