Check Isset In Javascript Code Example


Example 1: isset js

if (typeof obj.foo !== 'undefined') { }

Example 2: js isset

if (typeof obj.foo !== 'undefined') {   // your code here }

Example 3: check if isset variable js

var status = 'Variable exists'  try {   myVar } catch (ReferenceError) {   status = 'Variable does not exist' }  console.log(status)

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