1
SoftwareInfo result = new SoftwareInfo(
2
reader.GetString(1),              // reader 是 MySqlDataReader 实例
3
reader.GetString(7))
4
{
5
    ID = reader.GetInt32(0),
6
    Label = reader.GetString(2),
7
    Coder = reader.GetString(3),
8
    DownloadCount = reader.GetInt32(4),
9
    Stars = reader.GetFloat(5),
10
    Introduction = reader.GetString(6)
11
};
12

13
return result;

1
SoftwareInfo currentInfo = new SoftwareInfo(
2
reader.GetString(1),
3
reader.GetString(7))
4
{
5
    ID = reader.GetInt32(0),
6
    Label = reader.IsDBNull(2) ? null : reader.GetString(2),
7
    Coder = reader.IsDBNull(3) ? null : reader.GetString(3),
8
    DownloadCount = reader.IsDBNull(4) ? 0 : reader.GetInt32(4),
9
    Stars = reader.IsDBNull(5) ? 0 : reader.IsDBNull(5) ? 0 : reader.GetFloat(5),
10
    Introduction = reader.IsDBNull(6) ? null : reader.GetString(6)
11
};
12

13
return currentInfo;

1
alter table tablename modify columnname not null;