how to check if provided argument is null javascript 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 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).
}