>>I'v run into this problem before, and I hit it again tonight:
>>http://social.msdn.microsoft.com/Forums/en-US/csharpgeneral/thread/80ed858a-64e3-4821-a1a3-44940fbf4e83
>>
>>How about this for a solution - In my DataAccess class, whenver I receive a DbParameters collection, simply make a local copy of
>>each parameter, place each copy into a new collection, then assign that collection to the DbCommand object?
>>
>>This way, my collection of parameter never really gets used, like this:
>>
>>
>>

>>private List<DbParameter> _CopyParameters(List<DbParameter> Parameters)
>>{
>>    List<DbParameter> RetVal = new List<DbParameter>();
>>
>>    foreach (DbParameter Param in Parameters)
>>    {
>>        DbParameter NewParam = _Factory.CreateParameter();
>>        NewParam.ParameterName = Param.ParameterName;
>>        NewParam.Value = Param.Value;
>>        NewParam.Direction = Param.Direction;
>>
>>        RetVal.Add(NewParam);
>>
>>       Parameters.Remove(Param);
>>
>>    }
>>
>>    return RetVal;
>>}
>>

>>
>>Then use it like this:
>>

>>public int ExecuteNonQuery(string Command, List<DbParameter> Parameters, CommandType CommandType)
>>{
>>    int RetVal = 0;
>>
>>    DbCommand cmd = _GetCommand(Command);
>>
>>    try
>>    {
>>        RetVal = cmd.ExecuteNonQuery();
>>    }
>>    catch (Exception e)
>>    {
>>        throw;
>>    }
>>
>>    return RetVal;
>>}
>>

>>
>>Then in _GetCommand()...
>>
>>

>>private DbCommand _GetCommand(string Command, List<DbParameter> Parameters, CommandType CmdType)
>>{
>>    _GetFactory();
>>    _GetConnection();
>>
>>    DbCommand cmd = _Factory.CreateCommand();
>>    cmd.CommandText = Command;
>>    cmd.Connection = _Connection;
>>    cmd.CommandType = CmdType;
>>
>>    if (Parameters != null)
>>    {
>>        List<DbParameter> NewParams = _CopyParameters(Parameters);
>>
>>        cmd.Parameters.Clear();
>>        cmd.CommandType = CmdType;
>>
>>        foreach (DbParameter p in NewParams)
>>        {
>>            cmd.Parameters.Add(p);
>>        }
>>    }
>>
>>    return cmd;
>>}
>>
>>

>>
>>I implemented this and it seems to work. Thoughts?
>
>Could you organise things so that the parameter are removed after the command executes - that would mean you wouldn't need a copy everytime:

public int ExecuteNonQuery(List<SqlParameter> l)
>        {
>            SqlCommand sc = new SqlCommand();
>            foreach (SqlParameter p in l){sc.Parameters.Add(p);}
>            int RetVal = sc.ExecuteNonQuery();
>            foreach (SqlParameter p in l){sc.Parameters.Remove(p);}
>            return RetVal;
>        }

I tried your suggestion. It throws a runtime error "Collection was modified...."

Oh well. Nice try. Truth is, I'm not unhappy with my workaround.