How to Effectively Check for Empty Strings in JavaScript?

Checking for Empty Strings in JavaScript

The premise is to determine if JavaScript has an equivalent to string.Empty, or if checking for an empty string ("") suffices.

Truthiness and Falsiness

To examine for truthiness or falsiness, utilize logical operators:

• For truthy values: if (strValue){...} will be true if strValue is anything but an empty string, even true, 42, Infinity, or empty arrays.
• For falsy values: if (!strValue){...} will be true if strValue is an empty string, false, 0, null, or undefined.

Strict Equality for Empty Strings

To ascertain if a string is strictly empty, perform a strict equality comparison against an empty string ("") using the === operator:

if (strValue === ""){
  // Only if strValue is an empty string
  // (Not true for " ", "0", false, null, etc.)
}

Similarly, to determine if a string is not empty strictly, employ the !== operator:

if (strValue !== ""){
  // If strValue is anything but an empty string
}

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