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SqlDataReader Can't Proceed into While

I have a problem in SqlDataReader - it cannot proceed into while and cannot while.
Here is my code
List<tmp_WatchList> data = new List<tmp_WatchList>();
using (SqlConnection con = new SqlConnection(conStr))
{
using (SqlCommand cmd = new SqlCommand("sp_CheckPersonList", con))
{
try
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#Name", SqlDbType.NVarChar).Value = name;
SqlDataReader oReader = cmd.ExecuteReader();
while (oReader.Read())
{
//data.Add(new tmp_WatchList
//{
tmp_WatchList l = new tmp_WatchList();
l.id = int.Parse(oReader["id"].ToString());
l.Name = oReader.GetValue(1).ToString();
l.Crime = int.Parse(oReader.GetValue(2).ToString());
data.Add(l);
///});
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
con.Close();
}
}
}
and my stored procedure is:
ALTER PROCEDURE [dbo].[sp_CheckPersonList]
(#Name NVARCHAR(MAX) NULL)
AS
BEGIN
SELECT REPLACE(Name, '.', ''), Crime
FROM [dbo].[tmp_WatchList]
WHERE [Name] LIKE CONCAT('%', REPLACE(#Name, ' ', '%'), '%')
END
Can you tell me how it is done? Or is something wrong with my structure?

You are not opening the connection any where before calling the ExecuteReader, you need to open the database connection, following is the lineo of code to open the connection :
con.Open(); // open connection
SqlDataReader oReader = cmd.ExecuteReader(); // now execute SP
and you do not need finally block for closing the connection, as you are already applyuing the using block on your SqlConnection and SqlCommand which is converted by compiler in to try finally which takes care of disposing the resources and in case of SqlConnection closing the connection.

As other have pointed out, you need to Open the connection, and you can simplify your code removing the try/catch/finally and the explicit con.Close(), which you don't need since you are (corretcly) wrapping the connection within a using
Your code should be something like this (much cleaner than the original one after removing the try/catch/finally):
List<tmp_WatchList> data = new List<tmp_WatchList>();
using (SqlConnection con = new SqlConnection(conStr))
{
con.Open();
using (SqlCommand cmd = new SqlCommand("sp_CheckPersonList", con))
{
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("#Name", SqlDbType.NVarChar).Value = name;
SqlDataReader oReader = cmd.ExecuteReader();
while (oReader.Read())
{
tmp_WatchList l = new tmp_WatchList();
l.id = int.Parse(oReader["id"].ToString());
l.Name = oReader.GetValue(1).ToString();
l.Crime = int.Parse(oReader.GetValue(2).ToString());
data.Add(l);
}
}
}
If that code raises an exception, it will simply be forwarded to the caller, in a better way comparing to what you did with your throw new Exception(exc.Message), which will loose the original stack trace

Remove the unwanted code..Try Like this..
List<tmp_WatchList> data = new List<tmp_WatchList>();
SqlConnection con = new SqlConnection(conStr);
SqlCommand cmd=new SqlCommand();
cmd.CommmandText="sp_CheckPersonList";
cmd.CommandType = CommandType.Text;
con.Open();
cmd.Connection = con;
cmd.Parameters.AddWithValue("#Name",name);
SqlDataReader oReader = cmd.ExecuteReader();
while (oReader.Read())
{
tmp_WatchList l = new tmp_WatchList();
l.id = int.Parse(oReader["id"].ToString());
l.Name = oReader.GetValue(1).ToString();
l.Crime = int.Parse(oReader.GetValue(2).ToString());
data.Add(l);
}
oReader.Close();
Con.Close();

C# ASP.NET error: There is already an open datareader associated with this command which must be closed first

I keep getting this error
There is already an open datareader associated with this command which must be closed first.
at this line of code:
using (SqlDataReader rd = command.ExecuteReader())
I have tried to close all other SqlDataReader's in class but it didn't work.
public int SifreGetir(string pEmail) {
SqlCommand command = con.CreateCommand();
command.CommandText = #"SELECT Sifre FROM Kullanici WITH (NOLOCK) WHERE email=#email";
command.Parameters.Add("#email", SqlDbType.VarChar);
command.Parameters["#email"].Value = pEmail;
using (SqlDataReader rd = command.ExecuteReader())
{
rd.Read();
string pass = rd["Sifre"].ToString();
int p = Convert.ToInt32(pass);
return p;
}
}

Try implementing your code in the below format
using(SqlConnection connection = new SqlConnection("connection string"))
{
connection.Open();
using(SqlCommand cmd = new SqlCommand("your sql command", connection))
{
using (SqlDataReader reader = cmd.ExecuteReader())
{
if (reader != null)
{
while (reader.Read())
{
//do something
}
}
}
}
}
The using statement will ensure disposal of the objects at the end of the using block

try this:
public int SifreGetir(string pEmail) {
SqlConnection con = new SqlConnection("Your connection string here");
con.Open();
SqlDataAdapter da = new SqlDataAdapter();
DataSet ds = new DataSet();
SqlCommand command = new SqlCommand(#"SELECT Sifre FROM Kullanici WITH (NOLOCK) WHERE email=#email",con);
command.CommandType = CommandType.Text;
command.Parameters.Add("#email", SqlDbType.VarChar).Value = pEmail;
da.Fill(ds);
foreach(DataRow dr in ds.Tables[0].Rows)
{
string pass = dr["Sifre"].ToString();
int p = Convert.ToInt32(pass);
return p;
}
con.Close();
}

You have used Using Keyword for SQL Reader but There is nothing to take care of your command and connection object to dispose them properly. I would suggest to try disposing your Connection and command both objects by Using keyword.
string connString = "Data Source=localhost;Integrated " + "Security=SSPI;Initial Catalog=Northwind;";
using (SqlConnection conn = new SqlConnection(connString))
{
SqlCommand cmd = new;
cmd.CommandText = "SELECT ID, Name FROM Customers";
conn.Open();
using (SqlDataReader rd = command.ExecuteReader())
{
rd.Read();
string pass = rd["Sifre"].ToString();
int p = Convert.ToInt32(pass);
return p;
}
}

Error in server 'executenonquery requires an open and available connection'

I got this error on server not in local and when facing this error, then i re-upload that related class file. after doing this problem solved but not permanently.
Error:
executenonquery requires an open and available connection. The
connection's current state is open.
Code:
int n;
try
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.Connection = DataConnection.Con;
cmd.CommandText = "sp_InsertUpdateDeleteValidationDate";
cmd.CommandType = CommandType.StoredProcedure; cmd.CommandTimeout = 0;
cmd.Parameters.AddWithValue("#Task", "CheckExist");
cmd.Parameters.AddWithValue("#id", 0);
cmd.Parameters.AddWithValue("#AdId", "");
cmd.Parameters.AddWithValue("#Username", "");
cmd.Parameters.AddWithValue("#DOE", DOE);
cmd.Parameters.AddWithValue("#ExpieryDate", DateTime.Now);
cmd.Parameters.AddWithValue("#DOR", DateTime.Now);
cmd.Parameters.Add("#flag", SqlDbType.Int).Direction = ParameterDirection.Output;
if (cmd.Connection.State == ConnectionState.Closed)
{
cmd.Connection.Open();
}
cmd.ExecuteNonQuery();
n = Convert.ToInt32(cmd.Parameters["#flag"].Value);
return n;
}
}
catch (SqlException Ex)
{
return 0;
}

You only create one connection in your DataConnection class. You should create a new connection for each database call and let the driver's connection pooling take care of efficiently reusing them.
change your DataConnection class to this:
public class DataConnection
{
public static SqlConnection Con
{
get
{
return new SqlConnection(ConfigurationManager
.ConnectionStrings["conn"].ConnectionString);
}
}
}
and use a using statement when you use the connection like in ekad's answer:
using (SqlConnection conn = DataConnection.Con)
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.Connection = conn;
//use the command here
}
}

Looks like your SqlConnection is never closed. Try to use using statement to make sure that the SqlConnection is closed after executing cmd.ExecuteNonQuery()
int n;
try
{
using (SqlConnection conn = DataConnection.Con)
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.Connection = conn;
cmd.CommandText = "sp_InsertUpdateDeleteValidationDate";
cmd.CommandType = CommandType.StoredProcedure; cmd.CommandTimeout = 0;
cmd.Parameters.AddWithValue("#Task", "CheckExist");
cmd.Parameters.AddWithValue("#id", 0);
cmd.Parameters.AddWithValue("#AdId", "");
cmd.Parameters.AddWithValue("#Username", "");
cmd.Parameters.AddWithValue("#DOE", DOE);
cmd.Parameters.AddWithValue("#ExpieryDate", DateTime.Now);
cmd.Parameters.AddWithValue("#DOR", DateTime.Now);
cmd.Parameters.Add("#flag", SqlDbType.Int).Direction = ParameterDirection.Output;
conn.Open();
cmd.ExecuteNonQuery();
n = Convert.ToInt32(cmd.Parameters["#flag"].Value);
return n;
}
}
}
catch (SqlException Ex)
{
return 0;
}

running a simple query of sql server in c#

I am trying to run a test query using sql. I know it is a simple concept, but i have tried everything I could find online and the following does not even run. It shows no errors but it does not run.
private static SqlConnection conn = new SqlConnection("<connection string>");
public static void connect()
{
conn.Open();
SqlCommand command = new SqlCommand("spTester 'this is tested'", conn);
command.ExecuteScalar();
conn.Close();
}

It seems that you want something like that:
private static void connect() {
// static SqlConnection conn is a bad idea, local variable is much better
// Do not forget to dispose IDisposable: using(...) {...}
using (SqlConnection conn = new SqlConnection("<connection string>")) {
// Do not forget to dispose IDisposable: using(...) {...}
using (SqlCommand command = new SqlCommand("spTester", conn)) {
// You're executing procedure, not ordinal SQL
command.CommandType = CommandType.StoredProcedure;
// It seems, that you should provide a parameter to your procedure:
//TODO: Change "#ParameterName" to actual one
command.Parameters.Add(new SqlParameter("#ParameterName", "this is tested"));
// You don't need any result value be returned
command.ExecuteNonQuery();
}
}
}

public static void connect()
{
conn.Open();
SqlCommand command = new SqlCommand("spTester 'this is tested'", conn);
command.CommandType = CommandType.StoredProcedure;
SqlDataAdapter da = new SqlDataAdapter(cmd);
conn.Close();
}
try doing this..
as u probably forgot to mention command.CommandType = CommandType.StoredProcedure; line

this is a simple example it will let you get started using SQLCOMMAND
using (SqlConnection conn = new SqlConnection(connString))
{
SqlCommand cmd = new SqlCommand("SELECT * FROM whatever
WHERE id = 5", conn);
try
{
conn.Open();
newID = (int)cmd.ExecuteScalar();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
}

Try this :
public static void connect()
{
conn.Open();
SqlCommand command = new SqlCommand("spTester", conn);
command.CommandType = CommandType.StoredProcedure;
command.AddWithValue("#Parameter1","this is tested")
SqlDataAdapter da = new SqlDataAdapter(cmd);
conn.Close();
}

CA2000 object 'comm' is not disposed along all exception paths

I have a bunch of methods like so in my DAL in VS 2010. When I run the "new" Code Analysis option i get the message - Warning CA2000 object 'comm' is not disposed along all exception paths. Call System.IDisposable.Dispose on object 'comm' before all references to it are out of scope.
I understand I could use another using statement for the SQLCommand however if prefer to do it like I have with the Try/Finally block. My understanding is the Finally block executes last and does the cleanup. Does anyone see anything wrong here with my dispose call?
public List<Product> GetAllProducts()
{
List<Product> prodList = new List<Product>();
using (SqlConnection connection = new SqlConnection(GetConnection()))
{
SqlCommand comm = new SqlCommand("GetAllProducts", connection);
connection.Open();
comm.CommandType = CommandType.StoredProcedure;
SqlDataReader dr = comm.ExecuteReader();
try
{
while (dr.Read())
{
Product obj = new Product();
obj.ProductID = Convert.ToInt32(dr["ProductID"].ToString());
obj.Product = dr["Product"].ToString();
//etc....
prodList.Add(obj);
}
}
finally
{
comm.Dispose();
dr.Close();
}
}
return prodList;
}
}

If any of these three statements throw an exception, comm will not be disposed.
connection.Open();
comm.CommandType = CommandType.StoredProcedure;
SqlDataReader dr = comm.ExecuteReader();
Your try block would need to encompas these statements as well.

Put a using block around the command and dataReader so that they will always be disposed.
public List<Product> GetAllProducts()
{
List<Product> prodList = new List<Product>();
using (SqlConnection connection = new SqlConnection(GetConnection()))
{
using (SqlCommand comm = new SqlCommand("GetAllProducts", connection))
{
connection.Open();
comm.CommandType = CommandType.StoredProcedure;
using (SqlDataReader dr = comm.ExecuteReader())
{
try
{
while (dr.Read())
{
Product obj = new Product();
obj.ProductID = Convert.ToInt32(dr["ProductID"].ToString());
obj.Product = dr["Product"].ToString();
//etc....
prodList.Add(obj);
}
}
}
}
}
return prodList;
}

List<Measure_Type> MeasureList = new List<Measure_Type>();
SqlConnection conn = null;
SqlDataReader rdr = null;
SqlCommand cmd = null;
try
{
conn = new SqlConnection();
conn.ConnectionString = System.Configuration.ConfigurationManager.AppSettings["Conn"];
conn.Open();
cmd = new SqlCommand("SELECT Measure_ID, Mea_Name FROM MeasureTable WHERE IsActive=1", conn);
rdr = cmd.ExecuteReader();
if (rdr.HasRows == true)
{
while (rdr.Read())
{
MeasureTypeList.Add(new Measure_Type { MeasureTypeID = Convert.ToInt32(rdr[0]), MeasureTypeName = rdr[1].ToString() });
}
}
}
catch (Exception ex)
{
ExceptionPolicy.HandleException(ex, "Log");
}
finally
{
cmd.Dispose();
// close the reader
if (rdr != null) { rdr.Close(); }
// Close the connection
if (conn != null) { conn.Dispose(); }
}
return MeasureTypeList;
create conn = new SqlConnection(); inside the try block and then open it to solve this bug.