Java script 4

Conditional Statements 

JavaScript we have the following conditional statements:

• if

• else

• else if 

• switch 

   

  The if Statement

  Syntax

  if (condition) 

  {
      block of code to be executed if the condition is true
  } 

   

   Example : 

   <hmtl>

  <script>

  var age=20;

  if(age>18)

  {

  document.write("Qualifies for driving");

  }

  </scritp>

  </html>

  The else Statement

  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 : 

   <hmtl>

  <script>

  var age=20;

  if(age>18)

  {

  document.write("Qualifies for driving");

  } 

  else

  {

  document.write("doesnt qulify for driving");

  }

  </scritp>

  </html>

  
  

  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:Simillar to if else.
  

  The JavaScript Switch Statement

   

  Syntax 

   

   switch(expression)

   {
      case n:
          code block
          break;
      case n:
          code block
          break;
      default:
          default code block
  }