how to convert list to array or how to do this below code

Question

public class Emptab

{

public string rnumber;

public string sname;

public string depart;

public string active;

public string dsexecstatus;

public string dsmsg = "";

}

OdbcConnection odcon;

OdbcCommand comm;

DataTable dt = new DataTable();

string con = "Dsn=VD;uid=dba;password=sql";

 

public List<Emptab> insert(string[] as_connstring, List<Emptab> value)

{

 

 

List<Emptab> tDataList = new List<Emptab>();

Emptab tdata = new Emptab();

try

{

List<Emptab> arr = new List<Emptab>();

tdata.rnumber = arr[0].rnumber;

tdata.sname = arr[1].sname;

tdata.depart = arr[2].depart;

tdata.active = arr[3].active;

string ls_query="";

if (as_connstring[0] == "GET")

{

ls_query = @"insert into student values('" + arr[0] + "','" + arr[1] + "','" + arr[2] + "','" + arr[3] + "') ";

odcon = new OdbcConnection(con);

odcon.Open();

comm = new OdbcCommand(ls_query, odcon);

comm.ExecuteNonQuery();