If object is truthy, we already know that it is not null or undefined (assuming that the string values are a mistake). I assume that a not null and not undefined test is wanted.

JavaScript is very flexible with regards to checking for "null" values. I'm guessing you're actually looking for empty strings, in which case this simpler code will work:

If the purpose of the if statement is to check for null or undefined values before assigning a value to a variable, you can make use of the Nullish Coalescing Operator.

Jun 16, 2014 · Unless you want to specifically check for undefined or null. In which case val != null will return true for undefined or null but not for other falsey values like 0.

Oct 29, 2011 · However, this statement seems to return true when jso contains some null values, which is not what I want. Is there any method that can distinguish between a null JavaScript …

Dec 15, 2011 · A variable is a variable. It may refer to an object. Also, you may want to define "object" - as the answers and comments show, there are various conflicting definitions (e.g. …

It works on a null string, and on an empty string and it is accessible for all strings. In addition, it could be expanded to contain other JavaScript empty or whitespace characters (i.e. …

Apr 29, 2009 · In JavaScript, one difference is that null is of type object and undefined is of type undefined. In JavaScript, null==undefined is true, and considered equal if type is ignored.

Mar 25, 2009 · I think javascript should create something to check whether an object is empty or add length property to the object.

Feb 24, 2011 · (There's a difference between an object not having a property, and having the property with the value undefined; there's a difference between calling a function with the …