如果尚未上载所有文件，如何回滚

Question

Ok so i have a webform and 5 FileUpload control..a user can upload any number of files from 1 to 5 but if anyone of these files does not get uploaded then I want to rollback everything... For ex: if user has selected 4 files and if something unexpected occurs at 4th then I want to remove or rollback all the previous 3 file uploads.. I tried this..

 try
{
  using (TransactionScope scope = new TransactionScope())
                {
dboperation dbinsert=new dboperation();
if (file1.ContentLength > 0)
{
      .......
      .......
dbo.insert(bytes, lastid, file2.FileName);
}

if (file2.ContentLength > 0)
{
      .......
      .......
dbo.insert(bytes, lastid, file2.FileName);
}

if (file3.ContentLength > 0)
{
      .......
      .......
dbo.insert(bytes, lastid, file2.FileName);
}//till ...file5

scope.Complete();
}//end of transactionscope
}


catch { }

'dboperation' is a class in c# file and 'dbinsert' is a method which is executing an insert stored procedure. My guess is that I need to use Transaction Scope but I am not sure if I am correct and even if I am how am I supposed to achieve this?

Answer 1

You need to implement transaction . You should start the transaction before inserting first one and catch any errors that occur. in case of error you have to rollback the transaction. And if all goes well you can commit your transaction.

You should also move you connection outside the dboperation or make a method in dboperation that takes connection from outside and uses that

Answer 2

for this you need to use Transaction something like this. I give you example.

class WithTransaction
{
    public WithTransaction()
    {
        string FirstQuery = "INSERT INTO Table1 VALUES('Vineeth',24)";
        string SecondQuery = "INSERT INTO Table2 VALUES('HisAddress')";
        int ErrorVar = 0;
        using (SqlConnection con = new SqlConnection("your connection string"))
        {
            try
            {
                SqlCommand ObjCommand = new SqlCommand(FirstQuery, con);
                SqlTransaction trans;
                con.Open();
                trans = con.BeginTransaction();
                ObjCommand.Transaction = trans;
                //Executing first query

                //What ever operation on your database do here

                ObjCommand.ExecuteNonQuery();  //Exected first query
                ObjCommand.CommandText = SecondQuery;
                ObjCommand.ExecuteNonQuery();  //Exected first query
                //Everything gone fine. So commiting
                ObjCommand.Transaction.Commit();
            }
            catch (Exception ex)
            {
                Console.WriteLine("Error but we are rollbacking");
                ObjCommand.Transaction.Rollback();
            }
            con.Close();
        }
    }
}

Or you can use TransactionScope

check this Link

TransactionScope

I hope this will help you.