try catch的行为，最后是c＃中的return语句工作流

Question

I have little doubt about this try, catch and finally with return statement workflow...

This function is used to retrieve employee leave information for supervisor view. It works very well, but if there data found for if statement it will be return otherwise else block will be return. Even if the both get returns, its going to finally statement. I don't know why?

Code snippet here:

List<Leave> ILeaveData.GetLeaveForSupervisorView(int userID)
{
    SqlConnection con = new SqlConnection(_connectionString);
    SqlCommand cmd = new SqlCommand("Storeprocedurename", con);
    cmd.CommandType = CommandType.StoredProcedure;

    cmd.Parameters.Add(new SqlParameter("@Id", SqlDbType.Int));
    cmd.Parameters["@Id"].Value = userID;

    // Get employee leave information

    try
    {
        con.Open();
        DataSet ds = new DataSet();
        SqlDataAdapter adapter = new SqlDataAdapter();
        adapter.SelectCommand = cmd;
        adapter.Fill(ds);


        if (ds.Tables[0].Rows.Count > 0)
        {
            List<Leave> leave = new List<Leave>();
            for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
            {
                leave.Add(CreateLeaveForAdminViewFromDataRow(ds.Tables[0].Rows[i]));
            }
            return leave; // if data found then statement return here
        }
        else
        {
            return null; // otherwise return here
            // throw new Exception("Data Error");
         }
      }
      catch (SqlException err)
      {
          IErrorLog elog = new ErrorLog(_connectionString);
          elog.LogSystemError(err);
          throw new ApplicationException("Data Error", (Exception)err);
      }
      finally
      {
          if (con != null)
          {
              con.Close();
          }
       }
   }

regards Sarva

Answer 1

Finally statements are always executed, even if no exception occurs.

http://msdn.microsoft.com/en-gb/library/zwc8s4fz(v=vs.110).aspx :

Typically, the statements of a finally block run when control leaves a try statement. The transfer of control can occur as a result of normal execution, of execution of a break, continue, goto, or return statement, or of propagation of an exception out of the try statement.

Answer 2

finally块旨在始终执行，无论是否抛出异常。

Answer 3

在所有情况下都将执行最终块。