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c# - How to get float value with SqlDataReader?

In my database, I have NextStatDistanceTime value as a float. When "float time = reader.GetFloat(0);" line excecuted, it gives an error of

system invalid cast exception

How can I get float value from sql command in this code?

Here is my code:

using (SqlConnection conn = new SqlConnection(@"<myconnectionstring>"))
{
    float totaltime = 0;
    for (int i = startStationIndex; i < endStationIndex; i++)
    {
        SqlCommand command = new SqlCommand("SELECT NextStatDistanceTime FROM [MetroDatabase].[dbo].[MetroStation] WHERE StationIndex = " + i + "", conn);
        try
        {
            conn.Open();
            command.ExecuteNonQuery();
            using (SqlDataReader reader = command.ExecuteReader())
            {
                while (reader.Read())
                {
                    float time = reader.GetFloat(0);
                    totaltime = totaltime + time;
                    conn.Close();
                }
            }                        
        }
        catch (Exception ex)
        {
            result = ex.Message;
            Console.WriteLine(ex.Message);
        }
    }

}
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1 Answer

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by (71.8m points)

It's time for a little table, I think.

T-SQL type name .NET equivalent C# type name DataReader method
FLOAT System.Double double IDataReader.GetDouble()
REAL System.Single float IDataReader.GetFloat()

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