Test a string to be a valid date.
Test a string to be empty.
Test a string to be not empty.
Invert the following validators.
Test a string to be numeric.
Test a string to end with a specific value.
The value that should be the end of the string.
Test a string to be equal to a specified string.
Expected value to match.
Test a string to include a specific value.
The value that should be included in the string.
Test if the value matches a custom validation function. The validation function should return true if the value
passes the function. If the function either returns false or a string, the function fails and the string will be
used as error message.
Validation function.
Test a string to have a specific length.
The length of the string.
Test a string against a regular expression.
Test a string to have a maximum length.
The maximum length of the string.
Test a string to have a minimum length.
The minimum length of the string.
Test a string to start with a specific value.
The value that should be the start of the string.
Test a string to be alphanumeric.