Lesson 11: JavaScript Control and Loop Structure

• Control and Loop - refer to essential elements of programming that developers to manage the flow of a program and execute tasks efficiently.
• JavaScript Control - used to control the execution of a program based on a specific condition. If the condition is met, then a particular block of action will be executed otherwise it will execute another block of action that satisfies that particular condition.
• JavaScript includes if/else conditional statements to control the program flow.
• JavaScript If/Else Statements:

  • If Statement
  • If Else Statement
  • Else If Statement
• If Condition - use if conditional statement if you want to execute something based on some condition.

  
• Else Condition - use this statement when you want to execute the code whenever the condition evaluates to false.

  
• Else If Condition - use this condition when you want to apply second level condition after if statement.

  
• JavaScript allows multiple else if statements also.

  
• Switch Statement - is used for decision-making. It evaluates an expression, matches the expression's value against a series of case clauses, and executes the statements associated with the matching case.

  
• JavaScript Loop - are powerful tools for performing repetitive tasks efficiently. They execute a block of code again and again while the condition is true. They are used to execute a block of code repeatedly based on a condition.

  
• JavaScript Loop Statements:

  • For Loop
  • While Loop
  • Do While Loop
• For Loop - used when the number of iterations is known before entering the loop.

  
• While Loop - used when the number of iterations is not known beforehand. It continues to execute as long as the specified condition is true.

  
• Do While Loop - is similar to the while loop, but it guarantees that the code block is executed at least once before checking the condition.