javascript detect array code example

Example 1: if object is array javascript

Array.isArray(object);

Example 2: check if a variable is array in javascript

// inside if else check
if(Array.isArray(myVarToTest)) {
	// myVatToTest is an array
} else {
	// myVarToTest is not an array
}

Example 3: javascript test if it is an array

// If you want to test if a variable (object) is an instance of 
// an array. You can use the Array.isArray(varName) method
// this method takes one argument, the variable or object you want to test
// and returns true, if the argument is an array 
// or false, if the argument is not an array

if (Array.isArray(object)) {
	// is true
} else {
	// is false
}

Array.isArray([1, 2, 3, 4]); // Returns true
Array.isArray(4); // returns false
// this could be used for flattening an array of arrays

Example 4: how to recognize an array in javascript

const array = [1, 2, 3];

Array.isArray(array);  // => true
Array.isArray(object); // => false
Array.isArray(string); // => false
Array.isArray(empty);  // => false

// other ways

({}).toString.call(array);   // => '[object Array]'
({}).toString.call(object);  // => '[object Object]'
({}).toString.call(string);  // => '[object String]'
({}).toString.call(empty);   // => '[object Null]'