Slide 11.11: JavaScript if...else statements

Slide 11.10: JavaScript comparison and logical operators
Slide 11.12: JavaScript switch statement
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JavaScript if...else Statements

Conditional statements are used to perform different actions based on different conditions. JavaScript has the following conditional statements:

if, which executes some code only if a specified condition is true

if...else, which executes some code if the condition is true and another code if the condition is false

if...else if....else, which selects one of many blocks of code to be executed

switch, which selects one of many blocks of code to be executed

Note that if is written in lowercase letters. Using uppercase letters (IF) will generate an error. The else if and else parts are optional.

 if ( cond1 ) {
   to be executed if cond1 is true
 }
 else if ( cond2 ) {
   to be executed if cond2 is true
 }
 else {
   to be executed if cond1 & cond2 are not true
 }

The script checks the current minute:

The method getMinutes of the object Date returns the minutes, between 0 and 59, in the specified date according to local time.

The operator new creates an instance of a user-defined object type or of one of the built-in object types that has a constructor function.

Demonstration
The following demonstration shows how the script of HTML and JavaScript is displayed on the Web.

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Slide 11.10: JavaScript comparison and logical operators
Slide 11.12: JavaScript switch statement
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