新手问问petshop里面的一个问题 this._userid=userid

Question

public AccountInfo(string userId, string password, string email, AddressInfo address, string language, string category, bool showFavorites, bool showBanners) {
this._userId = userId;
this._password = password;
this._email = email;
this._address = address;
this._language = language;
this._category = category;
this._showFavorites = showFavorites;
this._showBanners = showBanners;
} // Properties
public string UserId {
get { return _userId; }
}
public string Password {
get { return _password; }
}
public string Email {
get { return _email; }
}
public AddressInfo Address {
get { return _address; }
}
public string Language {
get { return _language; }
}
public string Category {
get { return _category; }
}
public bool IsShowFavorites {
get { return _showFavorites; }
}
public bool IsShowBanners {
get { return _showBanners; }
}
}
this._userId = userId;  这句是什么意思？_userid 也没定义啊。见笑了。

Answer 1

应该在前面有定义的呀,就是把AccountInfo()方法中的参数据传递给_userId

Answer 2

private string _userId;
private string _password;
private string _email;
private AddressInfo _address;
private string _language;
private string _category;
private bool _showFavorites;
private bool _showBanners;
有定义，this._userid 是什么意思？

Answer 3

namespace PetShop.Model { /// <summary>
/// Business entity used to model accounts
/// </summary>
[Serializable]
public class AccountInfo { // Internal member variables
private string _userId;
private string _password;
private string _email;
private AddressInfo _address;
private string _language;
private string _category;
private bool _showFavorites;
private bool _showBanners; /// <summary>
/// Default constructor
/// </summary>
public AccountInfo() {
} /// <summary>
/// Constructor with specified initial values
/// </summary>
/// <param name="userId">Unique identifier</param>
/// <param name="password">Password</param>
/// <param name="email">Email address</param>
/// <param name="address">The default address object</param>
/// <param name="language">Prefered language</param>
/// <param name="category">Favourite Category</param>
/// <param name="showFavorites">Show customized favourites based on prefered category</param>
/// <param name="showBanners">Show personalized banners</param>
public AccountInfo(string userId, string password, string email, AddressInfo address, string language, string category, bool showFavorites, bool showBanners) {
this._userId = userId;
this._password = password;
this._email = email;
this._address = address;
this._language = language;
this._category = category;
this._showFavorites = showFavorites;
this._showBanners = showBanners;
} // Properties
public string UserId {
get { return _userId; }
}
public string Password {
get { return _password; }
}
public string Email {
get { return _email; }
}
public AddressInfo Address {
get { return _address; }
}
public string Language {
get { return _language; }
}
public string Category {
get { return _category; }
}
public bool IsShowFavorites {
get { return _showFavorites; }
}
public bool IsShowBanners {
get { return _showBanners; }
}
}
}完全的代码。