null or empty javascript code example

Example 1: javascript check if object is null or empty

if (typeof value !== 'undefined' && value) {
    //deal with value'
};

Example 2: javascript check for null variables

var myVar=null;

if(myVar === null){
    //I am null;
}

if (typeof myVar === 'undefined'){
    //myVar is undefined
}

Example 3: javascript null check

if (Var === null) { 
//code goes here
}

Example 4: javascript check if empty

//check if string is undefined 
if (typeof myVar === 'undefined'){
  console.log("I am not defined");
}

//check if string is empty, null, or 0
var emptyString="";
if (emptyString) {
    console.log("im not empty");
}