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database design question sangsram27-Dec-04 11:06 sangsram 27-Dec-04 11:06  My project is Car Rental Project. I hve some tables related to tbl-vehicle they are tbl-make, tbl-model and tbl-size make, model and size tables will hold ford, mustang and economy like wise my question here is,.... QUESTION 1 do i hve to store all the avaliable make and model of cars in my database , so that the user can select them accordingly when he add/buy a new car to the rental agency through vehicle transaction form (GUI). size wont be a matter becos there are some sizes like economy , standard etc.. and also i hve a table called tbl-booking to keep track of car bookings... i hve the following fields in that table... bookingid---autonumber bookstatuscode --- avaliable / booked cusid --- customer id vehreg --- vehicle registration fromdate -- pick up todate --- drop off confirmationletter --- yes/no paymentreceived -- yes/ no This booking table shld be my transaction table. QUESTION 2 here my question is do i hve to add something like payment type to customer table and do some billing transactions separately ...i dont know how to handle this...with the GUI...clear me.. i already finished developing the GUI for customer addition and updation. am now developing the GUI for Vehicle transaction. Re: database design question Dave Kreskowiak27-Dec-04 12:41 Dave Kreskowiak 27-Dec-04 12:41  This reeks of classwork... Only you can answer these questions. They depend entirely on your requirements. If you want the user to be able to select the make and model, then yes, they have to be in the database. Otherwise, the user will have to add them to the database using some other method so they can be selected at a later date. As far as your second question, why would you put a payment type on a customer record? This would normally be in a payment or billing transaction table... RageInTheMachine9532 "...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome Acrobat ActiveX VB programming evEddyG27-Dec-04 10:19 evEddyG 27-Dec-04 10:19  Does any have an example of programming the FindText method off the PDDoc object of the Adobe Acrobat ActiveX component model? How can i extract number from a Mobile SIM using TAPI using VB.NET Member 79618627-Dec-04 6:38 Member 796186 27-Dec-04 6:38  hello i want to extract a last recieved number from a mobile SIM using TAPI in VB.NET please help me as soon as possible thanx ps provide the answer with complete code plz Re: How can i extract number from a Mobile SIM using TAPI using VB.NET Dave Kreskowiak27-Dec-04 9:22 Dave Kreskowiak 27-Dec-04 9:22  AsadNeutron wrote: provide the answer with complete code plz We don't get paid to write code for other people. Try it yourself and if you have problems, you can ask specific questions about the problem your having. We help those who help themselves. You can start by reading SIM Programming with the .NET Compact Framework[^]. This explains how to use the SIM Manager API, which is part of the TAPI API. There is no TAPI support built into the .NET Framework, so you'll have to write your own wrapper classes, or search the web for a publicly available wrapper. RageInTheMachine9532 "...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome xgfhj Anonymous27-Dec-04 6:33 Anonymous 27-Dec-04 6:33  fth Best way to synchronize collection? carlos_rocha27-Dec-04 1:15 carlos_rocha 27-Dec-04 1:15  Hi! I would like to know what's the best way to accomplish sync. in an arraylist when using multiple threads. I' m using "synclock Coll.SyncRoot" and then "End synclock" (duh). Is this method rather "strong" for it blocks other threads that also use this? And what about if i use the synchronized method and the IsSynchronized property, is this approach better than the last case? Another question is i read in the help doc. that " Hashtable can safely support one writer and multiple readers concurrently". Won't the write affect enumerations done by the readers? Thanks in advance. Re: Best way to synchronize collection? Dave Kreskowiak27-Dec-04 5:10 Dave Kreskowiak 27-Dec-04 5:10  carlos_rocha wrote: I' m using "synclock Coll.SyncRoot" and then "End synclock" (duh). Is this method rather "strong" for it blocks other threads that also use this? It's supposed to block other threads. That's the whole point behind synchronized access. carlos_rocha wrote: that " Hashtable can safely support one writer and multiple readers concurrently". Won't the write affect enumerations done by the readers? If you keep reading the doc's, you'll see that enumeration is intrinsically not a thread-safe operation. This is because the collection can be modified while the eneration is taking place, and hence, can corrupt the enumeration process. If your going to enumerate the collection, lock it on SyncRoot first, preventing all other threads from doing anything, including writes, with the collection, though, I think you can figure out the pitfalls of doing this... If you want a synchronized collection that supports one writer and multiple readers simultaneously, use the .Synchronized() method to return a thread synchronized wrapper around your Hashtable and use this version of your Hashtable for all accesses. RageInTheMachine9532 "...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome Re: Best way to synchronize collection? carlos_rocha27-Dec-04 5:52 carlos_rocha 27-Dec-04 5:52  Hi! Thanks for your reply.The thing is that i have several threads but only two of them are acessing the arraylist, which contains info on the "working" threads.One of these two is like a monitor thread that checks every once in a while for exited threads and then removes an item from the arraylist.At the same time the other main thread in also reading the list and as new threads are created another node is added in the arraylist.So, only these two threads manipulate the arraylist.What's best? Use syncLock or .synchronized() ? Thanks in advance. Re: Best way to synchronize collection? Dave Kreskowiak27-Dec-04 9:07 Dave Kreskowiak 27-Dec-04 9:07  It really doesn't matter, based on the requirements you just gave. If that's all you're doing and one of those threads is just a lazy garbage collector, then there will be no performance issues with using either method. If it were up to me, I'd probably use the .Synchronized() method just to save myself from writing my own synchronization management code. RageInTheMachine9532 "...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome Re: Best way to synchronize collection? carlos_rocha27-Dec-04 22:04 carlos_rocha 27-Dec-04 22:04  OK.Thanks.I've been reading the help and i came upon the readerwriterLock Class.It says that it's suitable for various reads and infrequent writes, instead of blocking the code for the other thread, they both could acess the hash Table(or arrayList)...Any comments?Please... Thanks in advance. Never say never Problem with Access Briga26-Dec-04 23:30 Briga 26-Dec-04 23:30  Hi, I'm stuck with an Access (XP) DB. In the .mdb I have two tables, I load them in a dataset (with the same tables) and I work with the data. Up to here, everything is fine. To save back data in the DB I use a code I got from MSDN. Two different, but very similar, codes for each table. With one it works, not with the other! Here's the code: Dim conn As New OleDb.OleDbConnection Dim SelectCMD As OleDb.OleDbCommand Dim CustomCB As OleDb.OleDbCommandBuilder Dim DBAdapter As New OleDb.OleDbDataAdapter DB.AcceptChanges() conn.ConnectionString = String.Concat("Provider=Microsoft.Jet.OLEDB.4.0;Data source=", cfgDBDirectory, "\x.mdb") Try conn.Open() SelectCMD = New OleDb.OleDbCommand("SELECT * FROM Coordinate", conn) SelectCMD.CommandTimeout = 30 DBAdapter.SelectCommand = SelectCMD CustomCB = New OleDb.OleDbCommandBuilder(DBAdapter) DBAdapter.Update(DB.Coordinate) Catch ex As Exception MessageBox.Show(String.Concat("Errore nell'accesso alla base dati archivio:", ex.ToString), "RFGPRII", MessageBoxButtons.OK, MessageBoxIcon.Error) End Try End Sub The exception I got report a problem with the INSERT function. With the other table, code equal but table names, everything works! Thanks for the help Briga Re: Problem with Access Dave Kreskowiak27-Dec-04 4:45 Dave Kreskowiak 27-Dec-04 4:45  What is the EXACT exception message? Without it, there's nothing we can do to help you. My first GUESS would be that there was a problem with a duplicate primary key, but of course, I'm only guessing... RageInTheMachine9532 "...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome Re: Problem with Access Briga28-Dec-04 23:45 Briga 28-Dec-04 23:45  Well things are weird. I also added an XML just for text. So I load the DB with .readxml and before using the Update methos I also save it to an XML file with WriteXML. In the beginning I got problem with XML in reading (not in saving) due to invalid values. I changed every field as nillable and now it works (XML). The Update method doesn't generate any exception anymore but the .mdb is empty. The new code is: DB.AcceptChanges() DB.WriteXml("c:\RF.XML") ' *** salvataggio XML conn.ConnectionString = String.Concat("Provider=Microsoft.Jet.OLEDB.4.0;Data source=", cfgDBDirectory, "\rfgprii.mdb") Try conn.Open() SelectCMD = New OleDb.OleDbCommand("SELECT * FROM Coordinate", conn) SelectCMD.CommandTimeout = 30 DBAdapter.SelectCommand = SelectCMD CustomCB = New OleDb.OleDbCommandBuilder(DBAdapter) DBAdapter.Update(DB.Coordinate) Catch ex As Exception MessageBox.Show(String.Concat("Errore nell'accesso alla base dati archivio:", ex.ToString), "RFGPRII", MessageBoxButtons.OK, MessageBoxIcon.Error) End Try Now I also put a rem in front of the .writexml just to see if that instruction was affecting the Update. Still it generates no exception but the .mdb is empty. So to recap the exception was due to the nillable parameter (although there were no null values) and it's gone. The problem now is that the Update method does not work. The DB is empty. Any clues? Thanks for the reply Briga how to make a Modal Dialog in VB.net BSRK26-Dec-04 21:40 BSRK 26-Dec-04 21:40  can someone help me how to make my form like a MODAL DIALOG in VB.net application? Re: how to make a Modal Dialog in VB.net Jay Shankar26-Dec-04 22:20 Jay Shankar 26-Dec-04 22:20  Refer System.Windows.Forms.Form Class ShowDialog Method Re: how to make a Modal Dialog in VB.net Nasir_Awan27-Dec-04 8:32 Nasir_Awan 27-Dec-04 8:32  Any like named as Form1 Dim f as New Form1 f.Heights ... .... .... f.ShowDialog() set its diff properties n call ShowDialog() to show it Modally Re: how to make a Modal Dialog in VB.net Jay Shankar27-Dec-04 13:33 Jay Shankar 27-Dec-04 13:33  Your reply has come to me by mistake, Please reply to BSRK. creating rich text format file in vb6.0 Mohammad Daba'an26-Dec-04 20:24 Mohammad Daba'an 26-Dec-04 20:24  hi could any one help me---> i want to make a RTF file and insert a text in it and some icons that will be as a hypird threading when u click on it it will be opened and seen it can be image or word document or .... help me plz Thanks alot Metal Man Re: creating rich text format file in vb6.0 Jay Shankar27-Dec-04 13:37 Jay Shankar 27-Dec-04 13:37  The easiest way is to assign the formatted text and image in a RichTextBox and get the RichTextFormat string using Rtf property. Other way is to prepare rtf string as par RTF specification, the specification is available on msdn. How to load record to listview in vb.net Mekong River26-Dec-04 16:14 Mekong River 26-Dec-04 16:14  Hi, I have a table call tblTest in access with the following record. PersonalID PersonalName Sex 001 Bopha Female 002 Chantha Male I want to load these two record in a listview in VB.Net. Can anyone give me a sample code to load these two record in listview???? Note: I use vb.net. A thousand mile of journey, begin with the first step. APO-CEDC Save Children Norway-Cambodia Office Re: How to load record to listview in vb.net Mekong River27-Dec-04 16:18 Mekong River 27-Dec-04 16:18  I got it, I found the information from here.[^] A thousand mile of journey, begin with the first step. APO-CEDC Save Children Norway-Cambodia Office Rubber-Band Focus Rectangle OICU81226-Dec-04 13:51 OICU812 26-Dec-04 13:51  I'm searching for a VB.net example of a rubber-band rectangle or select rectangle using pinvoke ROP2 codes. I know about ControlPaint.DrawReversableFrame but im working in the .Net Compact Framework and that isn't in the compact framework. Also drawing to a bitmap and erasing it is inefficient for what im doing. I know an example is around here somewhere I just can't seem to find it. I had this all figured out a year ago in a project I shelved only now I can't find that project or all the code samples I produced. Passing events between forms plukje26-Dec-04 10:53 plukje 26-Dec-04 10:53  Passing events between forms Situation: I have: - a parent form with a toolbar with a button on it print (IsMidiContainer=true) - a child form within tis parent form - on this child form i place a usercontrol (with a tabbcontrol) Problem i want when i change to another tab in the tabbcontrol raising an event to the parent form where i can disable the button print when the user is on a tab where he can not print I can pass a event to a child form from a usercontrol but how can i pass this event to the parent form ?? (Public WithEvents childform as form, i cant find the event that i made) Somebody has a solution?? thx Greetz plukje Re: Passing events between forms carlos_rocha27-Dec-04 1:06 carlos_rocha 27-Dec-04 1:06  Hi! What i do is, after creating a new child form provide a handler in the main form: AddHandler newWindow.funcXXX, AddressOf funcHandler In the child form you have to declare an event and use raiseevent event2Use(parameters).

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