Get information from database

Get information from database

• braverwon

  I didn't get it.

  What's ToString

  Sorry, but I am a new of VB 2005

  
  

• Netklip

  They are in to toolbox. To be frank, this is about as detailed as the help here can get. If you're still having trouble, you probably need to take a step back and learn some fundamentals about the IDE and the language ( preferably via a book ) before trying to work with a database.

  
  
  

• User77

  Thank you David for your wondeful reply.

  But I am a beginner of VB 2005.

  I don't know how to drag a new Dataset and OleDbDataAdapter onto my form.

  Can you tell me how, please

  
  

• Brendan Kay

  // Ummm I use msgbox all the time.

  You're right. It 's in the VisualBasic namespace, a dll that exists to drag VB6 stuff into .NET. So, I've never seen it, as I use C# mostly. *blush*

  // But I'm really wondering if recordsets actually exit in ADO.NET.

  I think he's using ADO somehow. His original question was that the message box could not turn object into string, that's why I suggested using tostring, at the top of this thread. I only spotted the MsgBox thing today when I was trying to work out why he still had trouble.

  
  
  

• RobMiles

  Taking your example a line at a time.....

  Dim Con As New ADODB.Connection

  Drag a new OleDbConnection object onto your form... Name it "Con" if you like...

  Dim rst As New ADODB.Recordset

  Drag a new OleDbDataAdapter object onto your form... Name it "DBAdapter" if you like
  Drag a new Dataset object onto your form (Replaces your recordset) Name it "dst"...
  

  Set Con = New ADODB.Connection

  Define the connection string here for the "Con" object you added above
  Con.ConnectionString="Provider=MSDataShape.1;Extended Properties='Jet OLEDB:Database Password=111';Persist Security Info=False;Data Source=D:\Programs.mdb;Data Provider=MICROSOFT.JET.OLEDB.4.0"

  Con.Open "Provider=MSDataShape.1;Extended Properties='Jet OLEDB:Database Password=111';Persist Security Info=False;Data Source=D:\Programs.mdb;Data Provider=MICROSOFT.JET.OLEDB.4.0"

  In ADO.NET, the connection can be automatically opened as needed to read/write, improving access and sharing. (It doesn't have to, you can manually open/close a connection.) So no code needed for this line.

  rst.ActiveConnection = Con

  Ditto

  rst.Open "Select tab1.* from tab1 wehre tab1.Name='Example'"

  Define our adapter:
  DBAdapter.SelectCommand.CommandText = "Select tab1.* from tab1 wehre tab1.Name='Example'"

  Now Fill the dataset. (This opens the connection, reads, then closes it. Neat, huh )
  DBAdapter.Fill(dst)

  MsgBox rst.Fields("FileName")

  Umm, not sure if you can assign multiple fields at once.... If not, just use a for-next loop to build a string. Or simply make a listbox and assign the Datasource as Dst, and data member as your field "Filename".

  Thompson Course Technology has a nice easy book you can use to learn about databases in VB.NET: "Visual Basic .NET: An Object Oriented Approach." Very good examples, and it walks you through step by step.

  
  

• Hajin Studio Group

  First of all, MsgBox does not exist in VB.NET, unless it's one of these magic VB shortcuts. It's MessageBox.Show. Then, rst.Fields("Dir") probably needs to be cast to a string.

  I would recommend finding a website that covers the differences between VB6 and VB2005.

  http://www.google.com.au/search hl=en&q=vb6+VB.NET+2005+upgrade&meta=

  there seem to be a few in there.

  
  
  

• Sanjit Sachan

   

  "First of all, MsgBox does not exist in VB.NET, unless it's one of these magic VB shortcuts. "

  Ummm I use msgbox all the time in vs2005 VB.

  But I'm really wondering if recordsets actually exit in ADO.NET.

  I've been doing a lot of access and ADO.NET work lately and I seen rows but not record sets.

   

  
  
  

• Randaldtb

  OK

  Can you give me links and examples about ADO.NET, please

  Regards

  
  

• Norsek

  Assuming you want to keep using ADO, if the rest of this worked, then I would presume you just need to cast the value to string, probably by calling it's ToString() method.

  However, you'd do better to move your data access code to ADO.NET, if you can.

  
  
  

• MichaelEaton

  In ADO.NET, here are the general steps. (Compare these to your example above)

  Look on the Data tab of your toolbox to find these objects...

  1) Define a Connection object. (This specifices where your database is located, and how you are going to read from it, such as by using SQL)

  2) Define 1 or more Data Adapter objects (These determine which table(s) you will be pulling data from.)

  3) Define a dataset to store your information in. (Basically, a copy of one or more tables, but stored locally. ADO.NET allows you to work "offline" from your database, making additions, changes, and deletions, then you can save your changes all at once.)

  4) Use the Data Adapter Fill method(s) to fill your dataset

  5) You can bind the fields in your dataset to one or more controls like textboxes, datagrids, etc for ease of display or editing. (Using the DataSource to specify a table in your dataset, and Datamember to specify a record.) You can also work with items in the dataset directly, through programming. (To sum up the value of inventory, for example.)

  6) When you're done, you can write just those changes needing to be made back to your dataset.

  
  

• TheBouff

  ToString is a method that all objects in .NET support. It returns a string :-)
  
  

• Adam Norsworthy

  Msgbox definately exists in the VB.Net language

  Recordsets can exist if you are using ADO (which you can still use although for most purposes the features of ADO.NET allow things to be done better/simpler.

  But recordsets do not exist in ADO.NET object model.

  
  

• dealkk

  I can connect to database in VB 6.

  But I faced a trouble in VB 2005.

  VB 2005 didn't accept this line "MsgBox (rst.Fields("Dir"))"

  I don't know why.

  
  

• vpsdhillon

  http://msdn.microsoft.com/library/default.asp url=/library/en-us/cpguide/html/cpconoverviewofadonet.asp
  
  
• Get information from database