C# MySQL查询数据检索，尽管数据库中有数据，但所有内容都为空

正如我的问题所说，我在做一个mySQL查询，但是这个查询让我有些头疼，因为我试图从数据库中检索数据作为一个对象，这样我可以在javascript代码中重申，但是我从数据库中检索的数据都是null和0，尽管我的数据库本身没有null或0的值。我已将数据库值设置为不能为空。 这是我数据库中的值：

这是我检索到的数据。 {Musicid:0，Audioid:null，Description:null，MusicTitle:null，AudioPath:null，ImagePath:null，PriceType:null，UploadDate:\/Date-62135596800000\/，视图：0，Likes:0，NoOfReports:0，Type:null}

这是我的C班

public class music{
public int Musicid { get; set; }
public String Audioid { get; set; }
public String Description { get; set; }
public String MusicTitle { get; set; }
public String AudioPath { get; set; }
public String ImagePath { get; set; }
public String PriceType { get; set; }
public DateTime UploadDate { get; set; }
public int Views { get; set; }
public int Likes { get; set; }
public int NoOfReports { get; set; }
public String Type { get; set; }

public music(int musicid, String audioid, String description, String MusicTitle, String audioPath, String imagePath, String priceType, DateTime uploadDate, int views, int likes, int noOfreports, String Type)
{
    musicid = this.Musicid;
    audioid = this.Audioid;
    description = this.Description;
    MusicTitle = this.MusicTitle;
    audioPath = this.AudioPath;
    imagePath = this.ImagePath;
    priceType = this.PriceType;
    uploadDate = this.UploadDate;
    views = this.Views;
    likes = this.Likes;
    noOfreports = this.NoOfReports;
    Type = this.Type;
}

}

这是我的c代码

public List<music> Searchdatabase(String searchvalue)
{
    List<music> al = new List<music>();
    ArrayList array = new ArrayList();

    //sql connection, query values to database error need help
    string cs = ConfigurationManager.ConnectionStrings["test"].ConnectionString;
    using (MySqlConnection con = new MySqlConnection(cs))
    {

        con.Open();
        String query = "SELECT music.* FROM music WHERE MusicTitle LIKE @search";
        MySqlCommand command = new MySqlCommand(query, con);
        command.Parameters.AddWithValue("@search", "%" + searchvalue + "%");
        using (MySqlDataReader reader = command.ExecuteReader())
        {
            while (reader.Read())
            {
                if (searchvalue == null || searchvalue == "")
                {
                    break;
                }
                else
                {
                    al.Add(new music(reader.GetInt32(0), reader.GetString(1), reader.GetString(2), reader.GetString(3), reader.GetString(4), reader.GetString(5), reader.GetString(6), reader.GetDateTime(7), reader.GetInt32(8), reader.GetInt32(9) , reader.GetInt32(10), reader.GetString(11)));
                }
            }

            if (reader != null)
                reader.Close();
        }

    }
    return al;
}

该命令的工作方式似乎与我为searchbox值键入的任何内容一样，这是searchvalue，与数据库中与音乐无关的任何内容都不会为我提供任何正确的信息。但任何与musicTitle相关的内容都会返回对象数组，只要检索到的值为null和0，尽管数据库中有数据

---

我知道这可能会很长，希望有人能帮助我。谢谢

您的构造函数代码是错误的。您正在为构造函数参数赋值，而不是相反

public music(int musicid, String audioid, String description, String MusicTitle, String audioPath, String imagePath, String priceType, DateTime uploadDate, int views, int likes, int noOfreports, String Type)
{
    this.Musicid = musicid;
    ....
    this.NoOfReports = noOfreports;
    this.Type = Type;
}

另外，请查看对象初始值设定项，这样您就不会编写这些荒谬的构造函数

new music { Musicid = musicid, Type, NoOfReports = noOfreports .... };

---

在这种情况下，您甚至不需要构造函数。如您所见，如果变量名与属性名相同，则不必将其写成X=Y，而只需写成X。因此，它就像一个构造函数，但不必编写实际的构造函数。

您的构造函数将所有内容按相反的顺序编写。您正在设置参数而不是属性。将其更改为此，然后重试

public music(int musicid, String audioid, String description, String MusicTitle, String audioPath, String imagePath, String priceType, DateTime uploadDate, int views, int likes, int noOfreports, String Type)
{
    this.Musicid =musicid;
    this.Audioid = audioid;
    this.Description = description;
    this.MusicTitle = MusicTitle;
    this.AudioPath = audioPath;
    this.ImagePath = imagePath;
    this.PriceType = priceType;
    this.UploadDate = uploadDate;
    this.Views = views;
    this.Likes = likes;
    this.NoOfReports = noOfreports;
    this.Type = Type;
}

---

祝你学习顺利！调试器可能会为您节省很多时间。了解如何在正在开发的平台上进行调试。