Question

我这里有这个方法，它会让我从数据库中获取一个浮点数：

public List<AvidClass> getAvidByJob(string customerID)
        {
            AvidCell = new List<AvidClass>();

            connection = new SqlConnection(connectionString);
            command = new SqlCommand(@"SELECT construction, moveIn, yearEnd FROM AvidRating WHERE CustomerID = '" + customerID + "'");
            command.Connection = connection;
            command.Connection.Open();

            SqlDataReader dataReader = command.ExecuteReader();

            while (dataReader.Read())
            {
                AvidClass item = new AvidClass();

                item.construction = (float)dataReader[0];
                item.moveIn = (float)dataReader[1];
                item.yearEnd = (float)dataReader[2];

                AvidCell.Add(item);

            }
            connection.Close();

            return AvidCell;
        }

但是我收到了这个错误：

 Specified cast is not valid.

我做错了什么？

这是我的班级

public class AvidClass
    {
        public string community { get; set; }
        public string lot { get; set; }
        public int customerid { get; set; }
        public string user { get; set; }
        public float construction { get; set; }
        public float moveIn { get; set; }
        public float yearEnd { get; set; }
        public DateTime dateCreated { get; set; }
        public DateTime dateModified { get; set; }
        public string createdBy { get; set; }
        public string modifiedBy { get; set; }
    }

Answer 1

请尝试

Float.Parse(DataReader[0].toString());

尝试IDE的不同建议，你就会得到正确的建议。

Answer 2

尝试使用getfloat item.construction = reader.GetFloat（reader.GetOrdinal（＆＃34; 0＆＃34;））;

ASP.NET从数据库中获取浮动

2 个答案: