JavaScript: Return true if the string is y/yes other wise false

JavaScript fundamental (ES6 Syntax): Exercise-26 with Solution

Check y/yes or n/no in String

Write a JavaScript program that returns true if the string is y/yes or false if the string is n/no.

• Use RegExp.prototype.test() to check if the string evaluates to y/yes or n/no.
• Omit the second argument, def to set the default answer as no.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
// Define a function called `yes_No` that checks if the input string represents a "yes" or "no" value.
// It returns `true` for "yes", `false` for "no", and the default value if neither "yes" nor "no" is found.
const yes_No = (val, def = false) =>
  /^(y|yes)$/i.test(val) ? true : /^(n|no)$/i.test(val) ? false : def;

// Example usage
console.log(yes_No('Y')); // true
console.log(yes_No('yes')); // true
console.log(yes_No('No')); // false
console.log(yes_No('Foo', true)); // true (default value) 

Note: Omit the second argument, def to set the default answer as no.

Output:

true
true
false
true

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-1-26 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that returns true if a string equals "y" or "yes" (case-insensitive) and false for "n" or "no".
• Write a JavaScript function that normalizes input strings and checks for affirmative or negative responses.
• Write a JavaScript program that trims and lowercases a string before determining if it matches "y/yes" or "n/no".

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