check if null code example

Example 1: check if variable is undefined or null jquery

if (variable == null) {
    // variable is either null or undefined
}

Example 2: javascript check if null

if (variable === null) { //Executes only if variable is null but not undefined
  //Code here
}

if (variable == null) { //Executes if variable is null OR undefined
  //Code here
}

Example 3: js check null

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

Example 4: javascript check if undefined or null

// simple check do the job
if (myVar) {
 // comes here either myVar is not null,
 // or myVar is not undefined,
 // or myVar is not '' (empty string).
}

Example 5: moor check if null

..where((p) => isNull(p.end)))

Example 6: Null check

function exists (value) {
  return x != null ? Promise.resolve(value) : Promise.reject(`Invalid value: ${value}`)
}