Javascript只验证第一个变量而忽略其他变量

Question

尝试制作学校的通讯录，并输入两个字段并进行验证。似乎只验证第一个字段即名称，而忽略其余字段？我不确定是否有问题？它继续显示not a valid name作为错误消息，而没有其他显示。

var validate_birthdate = my.isBirthdateBad(add_birthdate);

if (!valid_name.test(add_name)) {
    alert("not a valid name");
    valid_contact = false;
} else if (add_address.length > 0) {
    if (!valid_address.test(add_address)) {
        alert("not a valid address: " + add_address);
        valid_contact = false;
    }
} else if (add_birthdate.length > 0) {
    if (!valid_birthdate.test(add_birthdate)) {
        alert("not a valid birthdate");
        valid_contact = false;
    }
  } else if (add_gender.length > 0) {
      if (!valid_gender.test(add_gender)) {
          alert("not a valid gender");
          valid_contact = false;
      }
    } else if (add_ocupation.length > 0) {
        if (!valid_occupation.test(add_occupation)) {
            alert("not a valid job title");
            valid_contact = false;
        }
} else if (validate_birthdate) {
    alert("not a valid birthdate: " + validate_birthdate);
    valid_contact = false;
} else if (!(add_photo !== undefined) &&
        (add_photo.length > 0) &&
        (add_photo.indexOf("data:image/jpeg") === 0)) {
    alert("image is not a jpeg!");
    valid_contact = false;
}

// note the use of the "anonymous" function
// this returns an array of all of the matched contacts! Powerful!
var exists = _address_book_contacts.filter(function (contact) {

    //check to see if the current "add_name"
    // is found in the address book!
    return contact.name() === add_name;
});

if (exists && (exists.length > 0)) {
    if (!confirm("WARNING: " +
            add_name +
            " exists in database. " +
            "Would you like to add again?")) {
        valid_contact = false;
    }
}