Distinguishing Null and Undefined Values and Understanding the Differences Between == and ===
Null vs. Undefined: Understanding the Absence of Values
In JavaScript, null and undefined play crucial roles in indicating the absence of values.
Checking for Null and Undefined
To determine if a variable is null, use any of the following options:
To check for undefined, consider the following:
Type Coercion with == vs. Strictly Equal with ===
The == operator performs type coercion to compare values, while === performs strict equality checks without type coercion.
For example:
"1" == 1 // True (type coercion converts "1" to 1) "1" === 1 // False (strict equality checks for same type and value)
The === operator is generally recommended for strict value and type comparisons.
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