Does the following code leave the connection open if there is an exception?
I am using a Microsoft SQL compact edition database.
try
{
SqlCeConnection conn = new SqlCeConnection(ConnectionString);
conn.Open();
using (SqlCeCommand cmd =
new SqlCeCommand("SELECT stuff FROM SomeTable", conn))
{
// do some stuff
}
conn.Close();
}
catch (Exception ex)
{
ExceptionManager.HandleException(ex);
}
Surely a better way would be to declare a connection object before the try, establish 开发者_JS百科a connection inside the try block and close it in a finally block?
SqlCeConnection conn = null;
try
{
conn = new SqlCeConnection(ConnectionString);
conn.Open();
using (SqlCeCommand cmd =
new SqlCeCommand("SELECT stuff FROM SomeTable", conn))
{
// do some stuff
}
}
catch (Exception ex)
{
ExceptionManager.HandleException(ex);
}
finally
{
if( conn != null ) conn.Close();
}
The way you are handling SqlCeCommand
in your code with the help of a using
block, you could do the same for the SqlCeConnection
.
SqlCeConnection conn;
using (conn = new SqlCeConnection(ConnectionString))
{
conn.Open();
using (SqlCeCommand cmd =
new SqlCeCommand("SELECT stuff FROM SomeTable", conn))
{
// do some stuff
}
}
Note: You can use a using
block for classes that implement IDisposable
.
EDIT: This is same as
try
{
conn = new SqlCeConnection(ConnectionString);
conn.Open();
SqlCeCommand cmd = conn.CreateCommand();
cmd.CommandText = "...";
cmd.ExecuteNonQuery();
}
finally
{
conn.Close();
}
ref: http://msdn.microsoft.com/en-us/library/system.data.sqlserverce.sqlceconnection%28VS.80%29.aspx
Use Using
using(SqlConnection conn = new SqlConnection())
{
//put all your code here.
}
try
catch
finally
is the proper way to handle this, because connection should always be closed at the end. but you should check not only that conn != null
, but also if conn
state is not Closed
.
You should use using
statement, which handles the connection closing without hassles
http://davidhayden.com/blog/dave/archive/2005/01/13/773.aspx
You Have To Try Following Way. Because Connection Close In Finally Block
try
{
SqlCeConnection conn = new SqlCeConnection(ConnectionString);
conn.Open();
using (SqlCeCommand cmd =
new SqlCeCommand("SELECT stuff FROM SomeTable", conn))
{
// do some stuff
}
}
catch (Exception ex)
{
}
finally
{
\\close connection here
}
Why not use a using
around the connection as well as the SqlCeCommand
?
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