A variable is undefined if it has not been assigned a value.
How do I determine if variable is undefined or null? My code is as follows: var EmpName = $("div#esd-names div#…
javascript jquery variables null undefinedWhat is the most appropriate way to test if a variable is undefined in JavaScript? I've seen several possible ways: …
javascript undefinedIs there a universal JavaScript function that checks that a variable has a value and ensures that it's not undefined …
javascript null comparison undefinedWhich method of checking if a variable has been initialized is better/correct? (Assuming the variable could hold anything (string, …
javascript variables initialization undefinedWhat's the best way of checking if an object property in JavaScript is undefined?
javascript object undefined object-propertyI wanted to check whether the variable is defined or not. For example, the following throws a not-defined error alert( …
javascript variables undefinedI have a global variable in JavaScript (actually a window property, but I don't think it matters) which was already …
javascript global-variables undefinedWe are frequently using the following code pattern in our JavaScript code if (typeof(some_variable) != 'undefined' && some_…
javascript null undefinedPHP is writing this error in the logs: "Notice: Use of undefined constant". Error in logs: PHP Notice: Use of …
php constants undefinedHow do I verify the existence of an object in JavaScript? The following works: if (!null) alert("GOT HERE"); But …
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