create a regular expression that will validate credit card expiry dates in format mmyy in javascript

To validate credit card expiry dates in format mmyy using regular expressions in JavaScript, you can use the following code block:

index.tsx
function validateExpiryDate(expiryDate) {
  // Regular expression to match mmyy format
  var regex = /^(0[1-9]|1[0-2])\/\d{2}$/;

  // Check if given expiryDate matches the regular expression
  return regex.test(expiryDate);
}
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This function takes a string argument expiryDate which represents the credit card expiry date in the format MMYY (eg: 0522 for May 2022).

The regular expression used in the function regex matches the format mmyy. Here, ^ and $ denote the start and end of the string respectively, () is used for grouping, | denotes OR condition, [] is a character set and \d is a shorthand character class representing digits 0-9.

The function test() is used to check if the given expiryDate matches the regular expression. If it does, true is returned, else false is returned.

You can call this function with expiryDate as an argument to validate the credit card expiry date.