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1. stackoverflow.com › questions › 2559318How to check for an undefined or null variable in JavaScript?

   stackoverflow.com › questions › 2559318

   If the purpose of the if statement is to check for null or undefined values before assigning a value to a variable, you can make use of the Nullish Coalescing Operator. According to the data from caniuse, it should be supported by around 85% of the browsers(as of January 2021). An example of the operator is shown below: const a = some_variable ??

2. www.freecodecamp.org › news › how-to-check-for-null-in-javascriptJS Check for Null – Null Checking in JavaScript Explained

   www.freecodecamp.org › news › how-to-check-for-null-in-javascript

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   29 lis 2022 · How to Check for Null in JavaScript with Equality Operators. The equality operators provide the best way to check for null. You can either use the loose/double equality operator (==) or the strict/triple equality operator (===).

3. stackoverflow.com › questions › 6003884How do I check for null values in JavaScript? - Stack Overflow

   stackoverflow.com › questions › 6003884

   To check for null SPECIFICALLY you would use this: if (variable === null) This test will ONLY pass for null and will not pass for "", undefined, false, 0, or NaN. Additionally, I've provided absolute checks for each "false-like" value (one that would return true for !variable).

4. expertbeacon.com › js-check-for-null-null-checking-in-javascript-explainedJS Check for Null – Null Checking in JavaScript Explained -...

   expertbeacon.com › js-check-for-null-null-checking-in-javascript-explained

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   24 sie 2024 · The key takeaways around properly checking for null values in JavaScript are: Use strict equality (===) to check explicitly for null values. Use loose equality (==) to check if values are null OR undefined. Leverage Object.is (value, null) for clear null checking.

5. developer.mozilla.org › en-US › docsnull - JavaScript | MDN - MDN Web Docs

   developer.mozilla.org › en-US › docs

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   25 wrz 2023 · null is not an identifier for a property of the global object, like undefined can be. Instead, null expresses a lack of identification, indicating that a variable points to no object. In APIs, null is often retrieved in a place where an object can be expected but no object is relevant.

6. masteringjs.io › tutorials › fundamentals`null` in JavaScript - Mastering JS

   masteringjs.io › tutorials › fundamentals

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   2 gru 2020 · Checking for null. You can check whether a value is null using the === operator: if (v === null) { // Handle `null` case here } You may also see == null. Using double equals with null is a shorthand for checking whether a value is null or undefined (so-called nullish values).

7. builtin.com › software-engineering-perspectives › javascript-null-checkHow to Check for Null in JavaScript

   builtin.com › software-engineering-perspectives › javascript-null-check

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   28 cze 2023 · When to Check for Null in JavaScript. The TypeError, “null is not an object”, can occur if the document object model (DOM) elements haven’t been created before loading the script. This can happen when the script is higher than the HTML on the page, which is interpreted from top-to-bottom.