javascript check type array code example

Example 1: javascript determine array type

var data = ['a', 'b', 'c']
var isArray = Array.isArray(data)
console.log(isArray)

Example 2: 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 3: typeof array javascript

//The method Array.isArray(A) checks if A is an array

Array.isArray([1, 2, 3]);  // true
Array.isArray('foobar');   // false for strings
Array.isArray({foo: 123}); // false for objects