not equal to empty array javascript code example

Example 1: javascript check if array is not empty

if (array === undefined || array.length == 0) {
    // array empty or does not exist
}

Example 2: javascript not empty array not string

if (Array.isArray(array) && array.length) {
    // array exists and is not empty
}

Example 3: check array empty or not in javascript

// To safely test if the array referenced by variable “array” isn’t empty:

if (array && array.length) {    
   // not empty  
} else { 
   // empty 
} 
// Note that if “array” is assigned to some other object that isn’t an array, the code will still execute the “else” part.

// A possible improvement to check that the object is specifically an empty array might be this:

if (array && array.constructor === Array && array.length === 0) {    
   // strictly an empty array 
} else { 
   // either null, or not an array or not an empty array 
}

Example 4: empty array javascript

let myArray = [12 , 222 , 1000 ];  
myArray.length = 0; // myArray will be equal to [].