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Okie.. sorry if my code was unclear..
I am converting some code from vb to c#, wch will take some values from Oracle database and will insert in to a MS access database..so I cant view the oracle database wch is in some other server.legseq field in oracle database is taking data dynamically , which can be empty also some times.
so while inserting in to Access database I need to check if the value of legseq is empty.if it is empty i need to make it Zero before inserting.
hope its clear now..
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You should almost certainly do this with DataAdapters and other useful things in System.Data instead of trying to convert the VB code verbatim. Handling of database nulls is something which I suspect will not work the same in the two environments anyway.
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Better 
My guess is that you need to check before you have the 'int leqseq' value.
Here are some things to look at:
- Can the value leqseq be null ? if so a nullable int (int?) or checking agains DBNull.Value is the best way to go.
then you can do this:
for int?
if(leqseq.HasValue){
}
else{
}
for checking against DBull.Value
- do you have a datatable, dataset, resultset somewhere?
in that case you can compare the database value against DBNull.Value.
if(mytable.Rows[rowindex]["columnname"] != DBNull.Value){
}
else{
}
If the value leqseq cannot be null in the database
you need to test if has an invalid 'value' like 0 or -1 or something, but this is bad database design. In that case you don't need a string either, but just compare against the 'fake' value.
Hope this helps.
V.
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I don't know how you are retrieving the values from the Oracle database, but ADO.Net DataReaders have an IsDBNull property, which can be used to check if a result is null, so you can do something like this :-
count = dr.IsDBNull(0) ? 0 : (int)dr[0];
and that will give you a 0 if the result is null, otherwise will return the value (assumes your data reader is dr).
When I was a coder, we worked on algorithms. Today, we memorize APIs for countless libraries — those libraries have the algorithms - Eric Allman
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yes .Thanks alot for the help
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The compile error message says it all. You cannot implicit compare integer datatype to string datatype
To get your code to compile you can use:
int legseq = 0;
if (legseq.ToStirng() == " ")
{
legseq = 0;
}
However, that if-statement will ALWAYS be false and legseq will never be assigned to 0.
What you're trying to do make no sense. You might be looking for:
int legseq = 0;
if (legseq != 0)
{
legseq = 0;
}
For me it looks like you have not looked and though over your program flow in your code.
/Steffe
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Hey there,
I am writing an owner drawn listbox control. This is based off of Mike Hankeys Extendable ListBox[^].
I have already modified his code greatly to fit my needs, but I would like the list box to 'auto-center' on the selected item when I click, and the index gets changed. As far as I can tell the only method for doing this is to modify the TopIndex. Is there any way to tell what indexs are viewable so I can just seek up/down a couple and say.. make sure this one is visible as well? Or am I just not looking at this correctly?
And while I am on the subject of scrolling. Any way to make it scroll smoother rather than jumping?
modified 12-Jan-12 12:29pm.
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Hi,
yes TopIndex is the way to go.
If the item height is constant (DrawMode.OwnerDrawFixed), the properties Height and ItemHeight should let you calculate how many items are visible at once.
if the item height is variable (DrawMode.OwnerDrawVariable) you had to provide a way to calculate the height (MeasureItem event), so you could use that method to decide how you want to spend your ListBox height.
For softscrolling, you would need access to the scrollbar itself and set its value, rather than TopIndex; I haven't done this, and I expect the ListBox to overrule you. You might have to replace the ListBox by a big-panel-in-autoscrolling-panel approach (this[^] could serve as a starter).
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Getting a list box to do exactly what I wanted was annoying enough that I wrote this control[^], which may be of use as an alternative starting point. I think scrolling was one of the things I had trouble with too.
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Hello,
I would like to wrap a text file into my project, and copy it out to a directory when a button is clicked. My current project is a dll plugin. Is there a way to have a folder inside of the solution explorer to hold these files, and then to be able to copy them out of this folder (which lives inside of the dll) to a directory?
If this is not possible, what is the most efficient way to write a text file, where carriage returns and spacing are crucial? It's a couple of hundred lines, so it'd be pretty tedious to write a string like the following which I was hoping to avoid and only use the below as a last resort.
string fileContentsLineByLine= "test" + System.Environment.NewLine +
"test2" + System.Environment.NewLine +
"test3";
Thank you for reading.
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You can add the file to your project's resources and access it from there at run time.
Unrequited desire is character building. OriginalGriff
I'm sitting here giving you a standing ovation - Len Goodman
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Thanks for the reply!
How can I reference it in the resources directory or is there a term for this I can google to see examples?
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Take a look at this MSDN article[^] for full details.
Unrequited desire is character building. OriginalGriff
I'm sitting here giving you a standing ovation - Len Goodman
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Thank you Richard! That article was very informative, although I have one more question.
I was able to get this to work with a bmp file, but I cannot seem to get it to work with a text file, or exe or dll?
With the bmp file, I can use the following code
System.Drawing.Bitmap bitmap1 = Project.Properties.Resources.bmppicture;
bitmap1.Save(theDirectory + @"\" + @"Fdr\bitmap1.bmp");
Scratch that, File.WriteAllBytes() works for txt files
Is there a way to Dllimport from an embeded dll that is inside of the resources folder?
modified 12-Jan-12 15:03pm.
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turbosupramk3 wrote: Is there a way to Dllimport from an embeded dll that is inside of the resources
folder?
Question isn't clear.
Given that you have a dll named X.
And you want to embed X into your application as a resource?
If the answer to that is yes then why would you want to do that?
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Hi,
I'd like to not only embed it as a resource, but load it into memory from the embedded location so that I don't have to copy it anywhere when I import it. This particular dll is unmanaged Delphi code, in case that matters.
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turbosupramk3 wrote: I'd like to not only embed it as a resource, but load it into memory from the embedded location so that I don't have to copy it anywhere when I import it. This particular dll is unmanaged Delphi code, in case that matters.
I doubt there is an reasonable reason for doing that. Some possible reasons.
- To 'protect' it.
- Unable to figure out how to access it.
- It won't run with the normal load
None of those are valid.
But regardless achieving it is going to be difficult. It is going to require a lot of code and lot of expertise and even an expert in several languages is going to have a difficult time getting it correct (bugs that do not cause failures.)
Some links that follow. (Keep in mind licensing concerns when looking at the code.)
http://delphi.about.com/od/windowsshellapi/a/delphi-load-resource-dll-into-memory.htm[^]
http://www.joachim-bauch.de/tutorials/loading-a-dll-from-memory/[^]
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You are right, this is more advanced then my skills ... thank you for the information.
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turbosupramk3 wrote: Is there a way to Dllimport from an embeded dll that is inside of the resources folder?
I have never heard of that. As far as I know the DllImport will expect to load a DLL from one of the library directories, so I don't know of any way it could be redirected to the resources. Also why would you wish to do such a thing, it seems over complicated.
Unrequited desire is character building. OriginalGriff
I'm sitting here giving you a standing ovation - Len Goodman
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You can extract any embedded resource (something compiled in with /res: in the compiler command line or with a build action selected as Embedded Resource in an IDE) with something along the lines of
Assembly.GetExecutingAssembly().GetResourceManifestStream(filename);
If you're using Visual Studio it has a horrible habit of prepending the default namespace on the front of all your resource files, so either (i) don't use VS or (ii) adjust all your resource-grabbing calls accordingly.
turbosupramk3 wrote: Is there a way to Dllimport from an embeded dll that is inside of the resources folder?
No. DllImport attributes are compile-time-bound to a file (though I'm not sure if the file actually has to exist at the appropriate time). You can load a managed DLL from resources using the byte[] overload of Assembly.Load, but to access an unmanaged one at runtime is something I don't know how to do. I would set the working directory of the application to a folder you have write access to and then copy the DLL you are trying to use in there when you run (or just include it in the deployment package).
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For completeness I am re-posting the following link up here.
It explains how one can load an unmanaged dll using a source besides a file. Note that this technique requires a high level of experience both in C/C++, windows architecture and file formats. And it is also likely that it could require changes based on things like OS version and probably for 64 bit formats.
http://www.joachim-bauch.de/tutorials/loading-a-dll-from-memory/[^]
But it is possible.
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Is there a support for serial ports in WinRT metro style application in the Developpers preview or is there going to be in the release version.
I need to communicate with our company proprietary device. In Windows CE I did it with Windows.IO.Ports.SerialPort and used FTDI USB to serial driver and dongle.
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Hi everyone,
im working on a project to detect car license plate using ABBYY FineReader Engine 10 SDK. And i would like to ask, how do i do closing on car license plate? Because i want to remove the protruding words and numbers from the car plates such that the image is 2D.
P.S, your answer is greatly appreciated And i do hope to get some sample codes as reference. Modifications will be done to given sample codes.
Thank you!!
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I hate to tell you, but no one is going to give you the source code. You're going to have to figure this one out yourself.
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Sadly, I have to create a COM object in C# that will be consumed by a PowerBuilder 11.5 application. Given some parameters, I need to return a byte array. I'm having trouble determining how to do this. I've tried including a ref parameter of type byte[]; no dice. I've tried declaring the parameter as "out"; again, no dice. I know the bytes I want to return are valid because I wrote them out to a file to verify. Can someone please tell me the best method to return a byte array to a calling application?
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