firstNameCode method
Implementation
String firstNameCode() {
String code = extractConsonants(this.firstName);
if (code.length >= 4) {
code = '${code[0]}${code[2]}${code[3]}';
} else {
code += '${extractVowels(this.firstName)}XXX';
code = code.substring(0, 3);
}
return code.toUpperCase();
}