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Khalid Kal

Khalid Kal

4 years ago

JavaScript Conditional Statements Tutorial with Example

The javascript conditions statements are the most used statements. When facing some conditional situations in programming, where a certain block of code to be executed when some condition is fulfilled.

In this javascript conditional statements tutorial, you will learn:

  • What are Conditional Statements?
  • Type of Type of JavaScript’s Conditional Statements
  • If statement
  • If…Else statement
  • If…Else If…Else statement

What are Conditional Statements?

Conditional statements are also known as decision-making statements. Which are used to making a decision and executes a block of codes based on certain conditions.

Type of JavaScript’s Conditional Statements

There are mainly three types of conditional statements in JavaScript that you can use to make decisions:

  • The if statement
  • The if…else statement
  • The if…else if….else statement

If Statement

The if statement executes a block of code if a condition is true.

Syntax

if (test condition)
{
    code to be executed if condition is true
}

FlowChart of If Statement

FlowChart of If Statement

Example of If Statement

Let’s take example for if statement and check only a specific condition using if statement:

<html>
<head>
  <title>IF Statments!!!</title>
  <script type="text/javascript">
    var num = prompt("Solve :- 8+5");
    if(num == 13)
    document.write("Correct answer <br />");
    if(num == 13)
    document.write("Wrong answer <br />");
  </script>
</head>
<body>
</body>
</html>

If Else Statement

When the if test condition evaluates to false. Then execute else statement block of code.

Syntax

if (test condition)
{
    code to be executed if condition is true
}
else
{
   code to be executed if condition is false
}

FlowChart of If Else Statement

FlowChart of If else Statement

Example of if Statement

Let’s take example for If Else statement:

<html>
<head>
  <title>IF ELSE Statments!!!</title>
  <script type="text/javascript">
    var num = 13;
    if(num == 12){  
      document.write("Execute If Statement<br />");
    }else{
      document.write("Execute Else Statement<br />");
    }
  </script>
</head>
<body>
</body>
</html>

If..Else If..Else Statement

When test multiple conditions after if statement. Then use Else If statement.

Syntax

if (test condition1)
{

code to be executed if condition1 is true

}
else if(test condition2)
{

lines of code to be executed if condition2 is true

}
else
{

code to be executed if condition1 is false and condition2 is false

}

Example of If Else If Else Statement

Let’s take example for if statement and check multiple conditions:

<html>
<head>
  <title>IF ELSE If Else Statments!!!</title>
  <script type="text/javascript">
    var num = 13;
    if(num == 12){  
      document.write("Execute If Statement<br />");
    }else if(num == 13){
      document.write("Execute Else If Statement<br />");
    }else{
      document.write("Execute Else Statement<br />");
    }
  </script>
</head>
<body>
</body>
</html>

#javascript #web-development

JavaScript Conditional Statements Tutorial with Example
17.85 GEEK