How do I check if a value is an empty or whitespace-only string in JavaScript without using regular expressions?
Benjamin C

To check if a value is an empty or whitespace-only string in JavaScript without using regular expressions, you can use the following approach: 1. Trim the string: Use thetrim() method to remove leading and trailing whitespace from the string. 2. Check the length: Use thelength property to check if the resulting string after trimming is empty. Here's an example:

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function isEmptyOrWhitespace(value) {
  // Trim the string
  const trimmedValue = value.trim();

  // Check if the trimmed value is empty or whitespace-only
  return trimmedValue.length === 0;
}

// Test cases
console.log(isEmptyOrWhitespace(''));              // true
console.log(isEmptyOrWhitespace('    '));          // true
console.log(isEmptyOrWhitespace('  hello  '));     // false
console.log(isEmptyOrWhitespace('hello'));         // false
console.log(isEmptyOrWhitespace('  hello'));       // false
console.log(isEmptyOrWhitespace('hello  '));       // false

In theisEmptyOrWhitespace function, we first trim the input string using thetrim() method, which removes any leading and trailing whitespace. Then we check if the length of the trimmed value is equal to zero, indicating that it is an empty or whitespace-only string. The function returnstrue if the string is empty or whitespace-only, andfalse otherwise. By using this approach, you can determine if a value is an empty or whitespace-only string without relying on regular expressions.