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the situation is that i have a table Employee info having attributes
EmpId
EmpName
GenID
the gender attribute is bieng filled by another table having 2 attribuites GenID and gender
i.e GenID is a foriegn key in the Employee info table
now when filling the table from a winform i loaded the data in the combo box of gender in form load event
but the value member is giving error bcoz i have to select the field from gender and must be saved in the Employee info table
sas
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Hello everyone.
I'm still in the process of learning C# (but not programming) so bear with me if this is something really trivial and a "duh" question 
How can I pass variables to a command button? For example, I'm working on an inventory/task system for work. I look up a laptop that has an asset tag of 740 for example, and on that Windows form I have a button that allows me to look up all tasks associated with that asset tag. My SQL query would be like "select * from tasks where asset_tag = '740'" but I don't know how to pass that SQL query the "740" piece. Hopefully this all makes sense and I haven't sounded like an idiot
Thanks guys!
Chip
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The asset tag value can be from a textbox or a dropdownlist, where a user can enter or choose a value, so what you need to do is to form the query:
"select * from tasks where asset_tag = '" + txtAssetTag.Text + "'"
where txtAssetTag is the said textbox.
By the way you should use parameterized query to avoid injection attack.
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Thanks darkelv.
Yeah I'm going to go with the parameterized query, just through up a quick example of what I was trying to ask  .
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darkelv wrote: "select * from tasks where asset_tag = '" + txtAssetTag.Text + "'"
No! NO! NO! NO! NO! NO!!!!
Never advise anyone in any way which would obviously lead to a SQL Injection Attack.
Please read SQL Injection Attacks and Tips on How To Prevent Them[^].
And yes, I know you suggested to use paramerised queries to avoid attack, but your sample should have used that from the off.
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Which is why I suggested him to use the parameter thingie in the end 
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All Controls have a Tag property which lets you store custom data.
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Hi
I have a problem while using the Filesystem watcher component in conjunction with a Windows form application.
I'm trying to do the following:
The form should show the content based on af file (which can be modified from another application!) and this should be done dynamically while the form runs...
So what I've done is to add a standard form to the app and then build the form contents dynamically based on the information contained in a file. The form contents is a panel and on that some labels and picture boxes...
So I would like to register a filesystem event monitor to detect when the file changes and re-create the Panels contents dynamically...now the problem occus...!
When trying to update the panel I get an error saying that:
Cross-thread operation not valid : Control 'pnlUpdates' accessed from a thread other than the thread it was created on.
The line of code that causes this error is:
pnlUpdates.Controls.Add(lblTest);
I suppose it is because the filesystem watcher is running in another thread and therefore this is not allowed?? I tried to use a backgroundworker to allow the update but this fails if I start the process from the OnChanged event of the Filesystem eventwatcher (same thread error as above)...
Anyone who knows how this can be done?
Kind regards
Thomas
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Must say I'm chuffed - I figured out the problem by reading just the subject. 
I had the same issue in a different context the other day; the problem is that Winforms controls are not thread safe. I'm not at work right now, so I don't have the code, but you will have to use a delegate in your form class to point to the method that actually does the work. In your event handler, you will have to invoke the delegate like
this.Invoke(new YourDelegate(TheMethodThatUpdatesTheControls)); The copy of MSDN on my colleague's machine was very helpful with this. If you're still having problems, just yell and I will give you the code when I get back to work tomorrow.
Cheers,
विक्रम
And sleep will come, it comes to us all
And some will fade and some will fall
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Hi
Thanks a lot for the help. Used the invoke method and it works like a charm!
Kind regards
Thomas
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tsiv wrote: Used the invoke method and it works like a charm!
It's not a charm. The behavior and solution are well documented. If you want to be a software developer rather than a snake charmer I strongly suggest you start reading the documentation.
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Don't you have something better to do than drop stupid comments on this forum!?
Fool.
I had a problem - Vikram was kind enough to point me in the direction of a solution - why do you even bother to give feedback if the feedback isn't worth anything...?? I don't understand that...
Thomas
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tsiv wrote: why do you even bother to give feedback if the feedback isn't worth anything...?? I don't understand that...
Of course you don't get it because you don't comprehend the value of reading the documentation. I can point that out to people like you but I can't make you understand it.
There is an old proverb, once again I can recite it but I can't make you understand it:
“Give a man a fish and you feed him for a day, teach a man to fish, and you feed him for a lifetime.”
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You might want to read this article. Hopefully it will clear up a lot of things: http://www.codeproject.com/csharp/begininvoke.asp
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Hello, I'm writing a ALT+TAB-ish app that pops up due to a hotkey. It currently displays a list of currently running applications (using EnumWindows & GetWindowText) as a row in a DataGridView and I've created a event handler to run when a row is double clicked on.
I'm hoping to use SetForeGroundWindow from User32.dll to bring the selected app to the front. This requires a pointer (IntPtr) to be passed, which I have available when populating my grid, but I can't see to keep around in IntPtr format. When I assign the IntPtr to a cell value, and then try to recast it as a pointer again, it bombs:
_hWnd = (IntPtr)dgvTaskList.SelectedRows[0].Cells[2].Value;
SetForegroundWindow(_hWnd);
I need to either
A) store a raw IntPtr in a cell (not as a string)
B) be able to convert the string back to a ptr
C) something else entirely that I'm not thinking of
I'm open to any help or suggestions from my code project peers...
Thanks!
-- modified at 12:13 Tuesday 27th November, 2007
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how about...
_hWnd = new IntPtr(int.Parse(dgvTaskList.SelectedRows[0].Cells[2].Value));
Jeff
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Holy cow man!
_hWnd = new IntPtr(int.Parse(dgvTaskList.SelectedRows[0].Cells[2].Value.ToString()));
..worked. Thanks!
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ive been using xptable, however, i have no clue as to how to add items to the combobox cell. has anyone figured this out? 
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What is xptable?
xacc.ideIronScheme a R5RS-compliant Scheme on the DLR
The rule of three: "The first time you notice something that might repeat, don't generalize it. The second time the situation occurs, develop in a similar fashion -- possibly even copy/paste -- but don't generalize yet. On the third time, look to generalize the approach."
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Dude, why don't you download the demo application. It will show you how to do exactly that.
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Yeah, i was going through it, and i must have missed it, but i figured it out now...
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how to know which procces['s] have access to a file in c#?
thnx
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