JavaScript Console Methods

Here are some commonly used JavaScript console methods for logging and debugging:

console.log()

This is the most commonly used console method, which logs messages to the console. It is used for general logging and debugging.

let a = 5;
console.log("The value of a is: " + a);

// Output: The value of a is: 5

console.error()

This method is used to log error messages to the console. It is used for logging and debugging errors in code.

let b = "hello";
if (typeof b !== "number") {
  console.error("b is not a number!");
}

// Output: b is not a number!

console.warn()

This method is used to log warning messages to the console. It is used for logging and debugging potential issues in code.

let c = 10;
if (c < 20) {
  console.warn("c is less than 20!");
}

// Output: c is less than 20!

console.time(), console.timeEnd()

These methods are used to measure the time it takes for a particular block of code to execute. They are used for performance testing and optimization.

console.time("timer");
for (let i = 0; i < 1000000; i++) {
  // some time-consuming operation
}
console.timeEnd("timer");

// Output: timer: 41.10400390625ms

console.table()

This method is used to display data in a table format in the console. It is useful for logging and debugging data structures such as arrays and objects.

let d = ["apple", "banana", "orange"];
console.table(d);

console.trace()

This method is used to log a stack trace to the console, which shows the path of execution that led to a particular point in the code. It is used for debugging complex code.

function foo() {
  console.trace();
}
function bar() {
  foo();
}
bar();

// foo
// @<anonymous>:2:9
// bar
// @<anonymous>:5:3
// @<anonymous>:6:1

Note that the output for console.trace() will vary based on the browser or environment used to run the code.