JAVASCRIPT

Control Structures


 

Control structures are essential for managing the flow of execution in JavaScript code. It allows developers to make decisions, iterate through data, handle errors, and create algorithms.

There are various ways to control structures:
 

1. IF…ELSE:

This control structure allows you to execute a block of code if a specified condition is true, and another block of code if the condition is false.

 

Example:

// switch
if(condition){
	// if condition is true
}
else{
	// if condition is false
}

 

2. SWITCH:

It allows you to select one of many code blocks to be executed.

 

Example:

// switch
switch(expression){
	case value1:
		// if exression matches value1
		break;
	case value2:
		// if expression matches value2
		break;
	default:
		if expression doesn't match any case
}

 

3. For Loop:

This control structure repeats a block of code a certain number of times.

 

Example:

// for loop
for(initialization; condition; increment/decrement){
	// code block to be executed
}

 

4. While Loop:

It repeats a block of code until the specified condition is true.

 

Example:

// while loop
while(condition){
	// code block to be executed
}

 

5. Do…While Loop:

It is similar to a while loop, but it executes the block of code once before checking if the condition is true, and then it will repeat the loop until the condition is true.

 

Example:

// do-while loop
do{
	// code block to be executed
} while(condition);

 

6. For…in Loop:

This loop iterates over the enumerable properties of an object.

 

Example:

// for-in loop
for(variable in object){
	// code block to be executed
}

 

7. For…of Loop:

It iterates over iterable objects like arrays, strings, …etc.

 

Example:

// for-of loop
for(variable of iterable){
	// code block to be executed
}

 

8. Try…catch:

This structure is used for error handling in JavaScript. Code in the try block is executed, and if an error occurs, it's caught in the catch block.

 

Example:

// try-catch
try{
	// code block to be executed
}
catch(error){
	// code block to handle the error
}

 

These control structures are fundamental in JavaScript programming and are used extensively to control the flow of execution in the code.