sqlConnection/Command using statement + try/catch block

Question

What is a correct approach try/catch inside using or using inside try/catch?

using (SqlConnection connection = CreateSqlConnection(connString))
{
               using (SqlCommand command = CreateSqlCommand()
               {
                   try{//open connection + execute command + do something else}
                   catch{//do something}
               }
}

vs.

try
{
    using (SqlConnection connection = CreateSqlConnection(connString))
    {
               using (SqlCommand command = CreateSqlCommand()
               {
                   //open connection + execute command + do something else
               }
    }
}
catch
{
 //do something
}

score 5 · Accepted Answer · answered Jan 15 '14 at 09:25

5

From my point of view:

try
{
    using (SqlConnection connection = CreateSqlConnection(connString))
    {
               using (SqlCommand command = CreateSqlCommand()
               {
                   //open connection + execute command + do something else
               }
    }
}
catch
{
 //do something
}

Above is the correct way.

Because , with this approach if there is exception with connection to database, that will get caught inside catch block.. But with first approach, it will not.

answered Jan 15 '14 at 09:25

C Sharper

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i also agree, but the using statment itself is questionable, doesnt it act similar to the try,catch and finally functions? if so, is there a need to wrap the using functions? – lemunk Jan 15 '14 at 09:27
But this doesn't speak against: `try{using(...){try{}}}`. Also, you are opening the connection **in** the `using`-statement and not outside, so why should i surround the using itself with a `Try-Catch`, that's a different scope. You are in danger to catch too much which is bad. – Tim Schmelter Jan 15 '14 at 09:32
but incase of choosing from one of the above from my point of view second one is better – C Sharper Jan 15 '14 at 09:38

score 1 · Answer 2 · answered Jan 15 '14 at 09:32

Both are correct in the sense that both will close the disposable resources in case of an error.

Where you place the try-catch-statement should depend on what you want to do with that information, i.e. if you want to react to an error concerning the SqlCommand itself or a more general SQL-error, that could also involve the connection.

score 1 · Answer 3 · answered Jan 15 '14 at 09:46

Personally, I think the best way is - then the connection is closed regardless and you get to handle the exception as you wish

using (SqlConnection connection = CreateSqlConnection(connString))
{
    using (SqlCommand command = CreateSqlCommand()) 
    {
          try { //open connection, execute }
          catch { // log and handle exception }
          finally { // check connection state and close if required }
    }
}

sqlConnection/Command using statement + try/catch block

3 Answers3

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