To check if a JavaScript array is empty or not, you can make either of the following checks (depending on your use case): const empty = !Array.isArray(array) || !array.length; const notEmpty = Array.isArray(array
The best way to check if an array is empty in JavaScript is by using the Array.isArray() method (ES5+) and array's length property together like so: // ES5+ if (!Array.isArray(array) || !array.length) { /
Example 2 : React check if string is null or empty In this second example of this tutorial, we use React JS to check if a string is empty or null using a simple condition. The condition is !str || str.trim() === "", which means that the string is either falsy (such as null,...
The falsy values in JavaScript are:null,undefined,0,false,""(empty string),NaN(not a number). If any of the six aforementioned values is to the left of the logical OR (||) operator, we return an empty array. If you can't track down where exactly the error occurred, look at your ...
is.empty(value:array|object|string) Checks if the given value is empty. is.existy(value:any) Checks if the given value is existy. (not null or undefined) is.truthy(value:any) Checks if the given value is truthy. (existy and not false) is.falsy(value:any) Checks if the given valu...
Array Date RegExp Null Undefined And there are some built inErrortypes as well. Things are a lot easier if we stick with the first diagram, though. Numbers Numbers in JavaScript are "double-precision 64-bit format IEEE 754 values", according to the spec. This has some interesting consequenc...
Array.isArray(hero); // => false Array.isArray(colors)returns a booleantrue, indicating thatcolorsis an array. 3. Falsy as type check undefinedin JavaScript is a special value meaning uninitialized variable. You can get anundefinedvalue if you try to access an uninitialized variable, non-exi...
Falsy values in JavaScript are:undefined,null,false, ,0,""(empty string),NaN(not a number). import{useEffect, useState}from'react'; export default function App() { const [message, setMessage] = useState(null); useEffect(() => {if(message) { ...
If we were creating an array, it would be an empty array. Next, we need to figure out what the parameters are for the function we pass to .reduce. In our example, we named them total and num. Remember, this function is going to be called for each element in the array. The reason...
_.isEmpty({1, 2, 3}) => false _.isEmpty({}) => trueisArray_.isArray(object)Returns true if object is an Array._.isArray({1,2,3}) => trueisObject_.isObject(value)Returns true if value is an Object. Note that JavaScript arrays and functions are objects, while (normal) ...