telephoneCheck function
Main function, str
will be the string of the number to validate and will return true or false
Implementation
telephoneCheck(String str) {
String pattern = r'(^[+]*[(]{0,1}[0-9]{1,4}[)]{0,1}[-\s\./0-9]*$)';
RegExp regExp = new RegExp(pattern);
if (regExp.hasMatch(str)) {
print('The number: $str you entered is valid');
return true;
} else {
print('The number: $str you entered is invalid');
return false;
}
}