locked
How to read data from database and store it in array RRS feed

  • Question

  • User1006710852 posted

    I am uisng asp.net 3.5 with c# as language. I want to read the database and store the data in either array or arraylist so that it can be called further in a dropdown list. How to proceed, pls give me some idea

    Wednesday, February 23, 2011 5:20 AM

Answers

  • User-1373473781 posted

    First make one class having similar attribute as you database table for eg:
            public class Student
            {
                public int ID { get; set; }
                public string Name { get; set; }
                public DateTime DateOfBirth { get; set; }
    
            }
    after that
                List<Student> student = new List<Student>();
                SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=D:\Prac\TestAssembly\ForumsProjectCSharp\App_Data\Studetnt.mdf;Integrated Security=True;User Instance=True");
                SqlCommand cmd = new SqlCommand("select * from Student", conn);
                SqlDataReader dr;
                try
                {
                    conn.Open();
                    dr = cmd.ExecuteReader();
                    while (dr.Read())
                    {
                        student.Add(new Student()
                        {
                            ID = dr.GetInt32(dr.GetOrdinal("ID")),
                            Name = dr.GetString(dr.GetOrdinal("Name")),
                            DateOfBirth = dr.GetDateTime(dr.GetOrdinal("DateOfBirth"))
                        });
                        
                    }
                    dr.Close();
                }
                catch (Exception exp)
                {
    
                    throw;
                }
                finally 
                {
                    
                    conn.Close();
                }
    
    Try this

    • Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM
    Wednesday, February 23, 2011 5:45 AM

All replies

  • User-1373473781 posted

    First make one class having similar attribute as you database table for eg:
            public class Student
            {
                public int ID { get; set; }
                public string Name { get; set; }
                public DateTime DateOfBirth { get; set; }
    
            }
    after that
                List<Student> student = new List<Student>();
                SqlConnection conn = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=D:\Prac\TestAssembly\ForumsProjectCSharp\App_Data\Studetnt.mdf;Integrated Security=True;User Instance=True");
                SqlCommand cmd = new SqlCommand("select * from Student", conn);
                SqlDataReader dr;
                try
                {
                    conn.Open();
                    dr = cmd.ExecuteReader();
                    while (dr.Read())
                    {
                        student.Add(new Student()
                        {
                            ID = dr.GetInt32(dr.GetOrdinal("ID")),
                            Name = dr.GetString(dr.GetOrdinal("Name")),
                            DateOfBirth = dr.GetDateTime(dr.GetOrdinal("DateOfBirth"))
                        });
                        
                    }
                    dr.Close();
                }
                catch (Exception exp)
                {
    
                    throw;
                }
                finally 
                {
                    
                    conn.Close();
                }
    
    Try this

    • Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM
    Wednesday, February 23, 2011 5:45 AM
  • User1992938117 posted

    it can be called further in a dropdown list.

    so why not you are binding dropdowllist directly:

    SqlConnection con = new SqlConnection("Server=CRC;Database=ABCD;Trusted_Connection=True");
    SqlCommand cmd = new SqlCommand("Select State from STATE");
    
    SqlDataAdapter objAdapter=new SqlDataAdapter();
    
    DataSet dset=new DataSet 
    objAdapter.selectCommand=cmd;
    
    objAdapter.Fill(dset,"state");
    
    con.close();
    dropdownlist1.DataSource=dset.Tables[0];
    
    dropdownlist1.DataTextField=dset.Tables[0].Columns[0].ToString()
    
    dropdownlist1.DataValueField=dset.Tables[0].Columns[0].ToString();
     dropdownlist1.dataBind();

    Wednesday, February 23, 2011 5:57 AM
  • User542821068 posted

               
                int[] _myArr = new int[NUMBER];
    where number is the field which u have fetched from database

    Wednesday, February 23, 2011 6:05 AM
  • User-1706566334 posted

    Hi,

     

    using DataTable retreview the data from Table, then create array list, convert the datatable value to string using " , ", then using split u can load the array list, if u load the value in DropDown list mean y u using Array List, from Data Table to Drop Down List u can directly load. no need for array list.

    EG Using Array:

    DataTable DT=new DataTable();
    string[] arr;
    if(DT.Rows.Count>0)
      {
           string StrArray = string.Join(",", (from DataRow row in DT.Rows select (string)row["DataTableColumnName"]).ToArray());
           arr = StrArray.Split(',');
       }

     

     

    Wednesday, February 23, 2011 7:36 AM