I am getting unable to store datatable value in string . How to return a string value of a data table? It gives an error while returning scalar value.

> 
> An exception of type 'System.IndexOutOfRangeException' occurred in System.Data.dll but was not handled in user code-- error in return statement 
> 
> 
> 

```
txtSalespersonName.Text = dl.GetStringValue("select top 1 [ContactPerson]  from tbl_Companies where Company='" +companyname + "' order by id desc");
public string GetStringValue(string query)
{
    DataTable dt = new DataTable();

    try
    {

        string constr = ConfigurationManager.ConnectionStrings["KernelCS"].ConnectionString;
        using (SqlConnection con = new SqlConnection(constr))
        {
            using (SqlCommand cmd = new SqlCommand(query))
            {
                using (SqlDataAdapter sda = new SqlDataAdapter())
                {
                    cmd.CommandType = CommandType.Text;
                    cmd.Connection = con;
                    sda.SelectCommand = cmd;
                    sda.Fill(dt);
                }
            }

        }

    }
    catch (Exception ex)
    {

      //  Response.Write(ex.Message);

    }
    return dt.Rows[1].ToString();
}

```