索引超出范围异常 - C＃

Question

I wanted to read the data from SqlDatabase but I'm getting the IndexOutOfRangeException, here is the screenShot of my table:

So here I have a function that gets the data from database and stores it into List of Lesson class, and i'm getting the exception in the lessons.Add():

 public List<Lesson> GetLessonsFromDay(string Day)
 {
    command.CommandText = "SELECT * FROM [Scadule] WHERE [day]='" + Day + "'";
    con.Open();

    SqlDataReader sdr = command.ExecuteReader();
    List<Lesson> lessons = new List<Lesson>();
    while (sdr.Read())
    {
        lessons.Add(new Lesson(Day, (int)sdr["[num]"], (string)sdr["[time]"],(string)sdr["[class]"],(string)sdr["[where]"]));
    }

    con.Close();
    return lessons;
 }

And here my lessonClass:

public class Lesson
{
public Lesson(string Day, int Num, string Time, string Class, string Where)
{
    this.Day = Day;
    this.Num = Num;
    this.Time = Time;
    this.Class = Class;
    this.Where = Where;
}

    public string Day { get; set; }
    public int Num { get; set; }
    public string Time { get; set; }
    public string Class { get; set; }
    public string Where { get; set; }
}

Answer 1

IndexOutOfRangeException will be thrown by the SqlDataReader[string name] overload if the column name you provide does not exist.

You are including [] braces within your column name string eg "[num]" , the column name might be just "num" , try to remove the braces and you should be good.

Answer 2

Try:

lessons.Add(new Lesson(Day, (int)sdr["num"], 
(string)sdr["time"],(string)sdr["class"],(string)sdr["where"]));

Answer 3

Instead of calling the columns by their names, try calling them by their index

Something Like this

while (sdr.Read()) { lessons.Add(new Lesson(Day, (int)sdr[1], (string)sdr[2],(string)sdr[3],(string)sdr[4])); }