ECMAScript Structure

Common program structures in ECMAScript include sequential, selection, iteration, and exception handling structures.

  1. Sequential Structure:
    The sequential structure is the simplest form of program logic, referring to executing statements one by one in the order they are written in the code. Common examples of this structure include variable declarations, assignment statements, function calls, etc.
let x = 10; // Variable declaration
let y = 20; // Variable declaration
let z = x + y; // Addition operation
console.log(z); // Output result
  1. Selection Structure:
    The selection structure determines which specific statements to execute based on a condition. Common examples of this structure include if and switch statements.
if (condition) {
  // Code block 1
} else {
  // Code block 2
}

switch (expression) {
  case value1:
    // Code block 1
    break;
  case value2:
    // Code block 2
    break;
  default:
    // Default code block
}
  1. Iteration Structure:
    The iteration structure repeatedly executes a group of statements until a specific condition is met. Common examples include for, while, and do-while loops.
for (let i = 0; i < 10; i++) {
  // Code block
}

while (condition) {
  // Code block
}

do {
  // Code block
} while (condition);
  1. Exception Handling Structure:
    The exception handling structure is used to capture and handle exceptions that occur during program execution. A common example of this structure is the try-catch-finally statement.
try {
  // Attempt to execute code
} catch (error) {
  // Handle the error
} finally {
  // Code executed regardless of whether an exception occurred
}

These program structures can be combined to build complex programs, such as nested loops and multiple selections. Mastering and flexibly using various program structures is key to writing efficient and maintainable code.