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why this code threw exception?
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim con As New OleDbConnection("provider=microsoft.jet.oledb.4.0;data source=c:\Degree.mdb")
Dim cmd As New OleDbCommand("select * from Student", con)
con.Open()
Dim sdr As OleDbDataReader = cmd.ExecuteReader()
Do While (sdr.Read = True)
Me.DataGridView1.Rows(0).Cells(0).Value = sdr(0)
Loop
sdr.Close()
con.Close()
con = Nothing
End Sub
the exception details
System.ArgumentOutOfRangeException was unhandled
Message="Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index"
ParamName="index"
Source="mscorlib"
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Without more information it's hard to tell, but I suspect that the table Student has records containing more than one value - ie StudentID, StudentLastName, StudentFirstName, etc. You are trying to shove all values of a record into a single cell of the DataGridView. Also, since you are using a loop to step through all the values in the DataReader, I assume you expect more than one student to be returned. Why, then, are you not providing an index to step through the rows and cells of the DataGridView? Instead, you are repeatedly assigning each record to the same row and cell.
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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You execute the reader and then you set a value into the datagrid. In what point the datagrid will have rows or cells?
The 'correct' way to do this is that you fill the datagrid using databinding, otherwise you have to create the columns and the rows to the datagrid manually. You can't just assign a value to a datagrid cell and expect that the framework creates a cell if it's not present.
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I need to fill Autocomplete textBox dynamically. any one have idea for that?
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Do use the search textbox at the top of this forum (I did a search on autocomplete textbox and found about 33 potential candidate articles). If I recall, there are a few articles floating around here on the subject. Good luck 
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
"Not only do you continue to babble nonsense, you can't even correctly remember the nonsense you babbled just minutes ago." - Rob Graham
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Jeez, gave him a good answer, no thanks and reposts. Some people, I swear 
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
"Not only do you continue to babble nonsense, you can't even correctly remember the nonsense you babbled just minutes ago." - Rob Graham
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Paul Conrad wrote: gave him a good answer
Agree (and 5'd)
Paul Conrad wrote: no thanks and reposts
Yeah, I know what you mean.
Gladly many people understand that the conversation goes both ways and this site is not somekind of paid support (it isn't... is it? Did my post office misplace the paycheck... Again  ).
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Mika Wendelius wrote: this site is not somekind of paid support
Yep.
Mika Wendelius wrote: Did my post office misplace the paycheck...
Go give your local postmaster hell, then 
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
"Not only do you continue to babble nonsense, you can't even correctly remember the nonsense you babbled just minutes ago." - Rob Graham
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yeah.. searched ...but no clues around Dynamic filling..
modified on Tuesday, December 9, 2008 11:46 PM
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SelvaSR wrote: but nothing is thr for multicolumn autocomplete textbox
possibly not, but then your original post never mentioned multicolumn did it, so why expect anyone to know that was what you wanted? However, a search on google for multicolumn autocomplete only returned around 29,000 results, the first 2 of which are articles here on CP, so I guess it would be difficult for you to find some ready written code, which I suspect you are really after.
Bob
Ashfield Consultants Ltd
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i have made setup of my project but i want to add copy protection like no body will able to copy cd or it will be installed only once like that so how can i do this?
Thanks & Regards,
Prashant B. Lavate
Software Engineer
Mobile : +919423872257
Pune(India)
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Well, not by cross posting. You need to look at licencing.
Bob
Ashfield Consultants Ltd
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Ashfield wrote: You need to look at licencing.
Just for conversation: Have you ever used a technique where you store part of your code at the server (which you own) and the client gets it at runtime in order to work (never stores it). So basically the installation is just part of the program, rest will come from the server if you're authenticated and licensed.
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No, although its sounds and interesting way of doing it. To be honest, for over 95% of my work the client gets the source code too, so I rarely have to worry about licencing.
Bob
Ashfield Consultants Ltd
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Yeah, I also think it's an interesting idea. Worth trying if you need to protect the source (and the executable also).
Ashfield wrote: over 95% of my work the client gets the source code too
After the payment I hope
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Don't cross post as it is considered rude. You did get some good replies in your other post. Do take a look at the discussion dan neely and I are having, there are some good clues in there 
"The clue train passed his station without stopping." - John Simmons / outlaw programmer
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
"Not only do you continue to babble nonsense, you can't even correctly remember the nonsense you babbled just minutes ago." - Rob Graham
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The saga continues...
I have finally got all the forms in place and loading in the proper order: Main -> Inventory -> Add Transformer -> Enter Transformer Info. The latter is implemented as a modal dialog with several text boxes for user entry and two list boxes for lookup from the database. I've bound the list boxes to the Volts table in the database to allow lookup of the permissible primary and secondary voltages, using the voltsBindingSource as the DataSource, and the Volts field of the Volts table as the DisplayMember, as instructed by the article in MSDN. The AllowDrop property is True.
What's confusing is that, when I first created the dialog box, running the code displayed the little dropdown arrow and showed all the entries in the table correctly. After fiddling with the navigation for a week or two, trying to get all the forms to display correctly - now working perfectly, thanks to several helpful members here - I no longer have the listboxes populated when I run the code. They look like a textboxes - no dropdown arrow, and no data displayed. I've checked the settings and they're still the same: DataSource=voltsBindingSource and DisplayMember=Volts.
What the heck am I missing here?
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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Roger Wright wrote: After fiddling
Roger Wright wrote: I no longer have the listboxes populated when I run the code.
Roger Wright wrote: What the heck am I missing here?
No way to know without being there. A general observation is that this is a good example of how software development requires understanding. Meaning it takes more than just following a set of instructions. Trying to skip ahead to finish without understanding all the individual technologies, constructs and concepts that one uses is a form of Technical Debt[^]. And when the debt comes due, it can be at a far greater interest rate than your typical credit card.
led mike
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led mike wrote: software development requires understanding
Obviously. And understanding arises from study, practice, and feedback. Having studied, and practiced, the notable lack of feedback is unenlightening. No errors, no messages, no nothing...
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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All your changes may be cumulative and somewhere in there is a problem that is screwing your display of combos. Now that your forms are navigating try and delete the combos from the form and add them again with different names (This is somewhat like making sure your tounge is pointed the correct way and the wind is blowing from the east). Rebind the combos
Never underestimate the power of human stupidity
RAH
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That's essentially what I did late last night, though it was with listboxes, rather than comboboxes. To be thorough, I also removed the data source from the project, then re-added it and bound the target table to the controls as I added them back into the dialog. That made it work properly, except that although the listbox AllowDropdown property is True, they don't drop down at runtime. Oh well, that was enough progress for one night. I need to get a reference I can study that includes details of all the properties of the .Net controls and how to correctly use them.
I then studied the code changes and found an autogenerated line that called the TableAdapter.Fill method, which I must have inadvertently deleted earlier in my experimenting with navigation. I had searched the source code several times previously trying to find where the data was loaded and never located it. Now I know why, and how to fix it in the future.
Two things I'm finding difficult to deal with are the design philosophy of VS and MSDN. The separation of code using a partial class to maintain a master file and a designer file makes life easier in some ways (especially for Wizard designers), but makes understanding the code more difficult. Having all the code in one place makes it cluttered, but I find it much easier to grasp the whole and analyze my mistakes. Relying on MSDN as my main source of learning is crippling, as it tends to be focused on step-by-step procedures - many incomplete or just plain wrong - and leaves out the conceptual material needed to fully grasp the meaning of each step. It doesn't help that, no matter what filters I select, a search always returns far more unrelated content than useful material.
Thanks for the guidance!
"A Journey of a Thousand Rest Stops Begins with a Single Movement"
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Roger Wright wrote: Relying on MSDN as my main source of learning is crippling, as it tends to be focused on step-by-step procedures
Yes. That is documentation, very rich by comparison to other vendors, but still just documentation. What you seem to be missing is Design. You seem to be missing Design aspects like Model-View-Controller[^], more commonly referred to as Design Patterns. This is what I was talking about in my first reply to this thread. Object Oriented Principles, Best Practices, OO Design and Design Patterns are things that one needs to study and understand so they can be leveraged to simplify the complex, to the degree that it can be simplified of course. Studying these aspects of Software Development is not comparable to reading documentation.
led mike
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I have a C# Windows Forms app in which there are a number of Panels containing standard controls like PictureBox'es, Buttons and Labels. At runtime, I allow the user to drag-and-move the panels to reposition them where he/she likes. I programmed my own drag-around logic using MouseDown, MouseMove, and MouseUp.
While the user drags the Panels around, there is considerable unpleasant flickering.
Where does the flickering come from? Anything I can do to eliminate it?
THANKS!
Mark
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