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Hi,
we implemented an application, where we designed the architecture like an example given by Microsoft. This architecture uses different layers, so that the presentation layer don't know where the data comes from (like it should be or?). The dataaccess component packages everything into small objects which will be transferred by the business logic to the presentation layer. There we put these objects into a datatable and display the datatable with a DataGridView.
The problem that we have now is, that the application should deal with a large amount of data. This is very slow, because the application puts all the data into the small objects. I read something about the virtual mode of a DataGridView, but this seems to be useful only if you are operating directly with a database. So my question is, does anybody had something similar, and how did you solved it?
Regards
Sebastian
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I need to change properties of controls from an external dll
for eg. i have an app. which contains a textbox(textbox1) and references abc.dll
how can i change textbox1.text from abc.dll? Please help.
Thanks in advance.
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You shouldn't be doing that. Unless the library is specifically for the purpose of manipulating forms, it shouldn't care about what controls are on a form.
If you're trying to return a value, return it to the caller in the form code and let the form code be responsible for updating the controls.
Dave Kreskowiak
Microsoft MVP - Visual Basic
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Thanks a lot for ur reply... appreciate that...
actually what i want to do is this:
i have my application referencing a library.
the application has a progressbar and status bar
the library compiles other solutions(devenv .....) in the background (+ does a few other tasks) and i need it to update the status bar and progress bar
if it would be just text... it wouldnt b a problem to return the text and update textboxes accordingly.
but the progressbar is the problem... thers no point if it gets updated after everything is over..
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It could fire events to say that the status has changed. Something else could then handle the event and update the form accordingly.
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Hello everyone, I have a form and a picture, and i want the picture to "hang" off of the form. I have tried making the background of the picture transparent, and making a background with a special color for transparency, but the image has a shadow and the color continues to show up in the shadow when it is run. What should I do differently to get this to work? Thanks.
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The image is probably a jpeg. JPEG images use lossy compression, so the color that was solid, is now a range of colors in that general vicinity. Draw the image yourself on your background, in a paint event handler. Use the ImageAttributes class as a parameter when drawing the image, and you can specify a range of colors to make transparent.
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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Hi, I am writing a program in C#, and I want a customize form to pop up. I created the new form and set it up as a new item (Form frmCustomize = new Form();). So then, in my code, I put this code in for when they click on Customize, and the form shows, but none of the controls are there, any reasons why, or any help?
The code:
// When they click 'Customize' from the help menu the Customize form shows
private void customizeToolStripMenuItem_Cli... sender, EventArgs e)
{
// Show the customize form
frmCustomize.Show();
}
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Wolf92 wrote: Form frmCustomize = new Form()
This creates an instance of the base class Form, not the form you created. You have to do something like this:
private Form customiseForm = new CustomiseForm();
Note: I've assumed your customise form class is called CustomiseForm. I've also assumed that you expose no new public functionality. If you do (and it most likely is that you do) then you may wish to declare the customiseForm field as a CustomiseForm rather than a simple Form.
Does this help?
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Wolf92 wrote: Form frmCustomize = new Form()
That creates an empty form, which is what you're seeing. You probably meant to do:
Form frmCustomize = new CustomizeForm();
/ravi
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Hello everybody , any help will be greatly appreciated.
======================================================
i have a dll file that contains a compression algorithm this compression is speex , you can search it by googling it.
the file is called libspeex.dll.
i tried to add it as reference in my project but the studio enables only assembly files and COM files only.
the question is :
can i put this file in the same path of the application i mean in the "debug" folder to be able to export methods from it ????
and if i used
[DllImport("libspeex.dll")]
in my code and tried to export methods will it read the libspeex.dll or it will not find it .
i just wonder because i am always using to put in the parameter of the dllimport() attribute any dll file from system32 but i never used to put a local file into it
please can anybody help me ? if this method will work or if not ,how can i export functions from this unmanaged file.
Human knowledge belongs to the world.
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Put the DLL in your project (Add Existing Item). When it appears, right click it and select properties. In the properties marking it as "Content" and "Copy Always". That will ensure it is copied to your Debug folder and Visual Studio keeps track of it through the project. It will also get added automatically to any set up projects you create.
snouto wrote: [DllImport("libspeex.dll")]
in my code and tried to export methods will it read the libspeex.dll or it will not find it .
The DLL must be in the Current Path at run time in order for your application to find the DLL. You can specify a full path name, but if the DLL is subsequently moved then you'd have problems.
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Hi,
I have an interesting scenario.
I’m trying to pass a GUID to my Sql Parameter in a Stored procedure.
First I added the parameter:
command.Parameter.Add(new SqlParameter(“@myID", UniqueIdentifier, 0));
Now, my problem..
The myID GUID comes from a textbox which I generate a Guid.NewGuid() for.
When I try to set the parameter value like this:
command.Parameter[0].value = textbox.Text;
No this doesn’t work because textbox.Text is a string and therefore the compiler complains when I try that.
I have then tried to cast textbox.Text to a GUID like this:
command.Parameter[0].value = (Guid)textbox.Text;
No once again the compiler complains cause it wont let you cast a string to a Guid.
Any ideas for me please?
Thanks.
R
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Hi,
what is the easiest method to copy one byte array to another... but not all, only a part. Let say that we have :
byte[] a = new byte[]{1,2,3,4,5,6,7,8,9,10};<br />
byte[] b;
how to copy to array b bytes from array a but from offset 2 to 6 only.
I know that can use for loop but maybe there is better method?
Greetings
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Take a look at the Array.Copy method.
"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning." - Rick Cook www.troschuetz.de
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Application is compiled well but when run i got error like:
Could not load type 'Test.EF' from assembly ... because it contains an object field at offset 1 that is incorrectly aligned or overlapped by a non-object field.
<br />
[StructLayout(LayoutKind.Explicit)]<br />
public struct EF<br />
{<br />
<br />
[FieldOffset(0)]<br />
public byte clockStop;
[FieldOffset(1)]<br />
private byte[] cardExtendedSerialNumber;
[FieldOffset(8)]<br />
private byte[] cardApprovalNumber;
[FieldOffset(16)]<br />
private byte cardPersonaliserID;
[FieldOffset(17)]<br />
private byte[] embedderIcAssemblerId;
[FieldOffset(23)]<br />
private byte[] idIdentifier;
<br />
};<br />
Any idea how fix it?
Greetings
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yarns wrote: [FieldOffset(1)]
private byte[] cardExtendedSerialNumber; //8
[FieldOffset(8)]
1 + 8 = 9
---
single minded; short sighted; long gone;
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What do you mean exactly by "dont work"?
Do you get any error message?
What does your code look like now?
---
single minded; short sighted; long gone;
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1)
when you write byte[] you are declaring a reference type, you can think of it as a pointer
to some (yet unallocated) piece of memory. Such pointer needs 4 or 8 bytes of storage
(depending on you using Win32 or Win64) and independent of the amount of data you expect
your array to hold; also the pointer must be properly aligned (the offset
must be a multiple of 4, maybe of 8). Some of your arrays do not satisfy the alignment
requirment, and that explains the error code you are getting (its an align error,
not an overlap error).
2)
I suspect you really want your struct to hold some 25 bytes, and its layout to be
fixed (either by some hardware, or by a file format). If so, you must do it
differently; I see basically two possible approaches:
a) replace the struct by a single byte array, and take care of the offsets within your
code. This is the unstructured approach.
b) replace the struct by a combination of simple variables and other structs (which
again are limited to value types such as ints and value-only structs); and you could
and should teach those sub-structs how to interpret the data; could be something like (not correct, just indicative):
public struct string8 {
public byte b0, b1, b2, b3, b4, b5, b6, b7;
public string8(string s) {
b0=0; b1=0; b2=0; b3=0; b4=0; b5=0; b6=0; b7=0;
if (s==null) return;
if (s.Length>=1) b0=(byte)s[0];
if (s.Length>=2) b1=(byte)s[1];
if (s.Length>=3) b2=(byte)s[2];
if (s.Length>=4) b3=(byte)s[3];
if (s.Length>=5) b4=(byte)s[4];
if (s.Length>=6) b5=(byte)s[5];
if (s.Length>=7) b6=(byte)s[6];
if (s.Length>=8) b7=(byte)s[7];
}
public override string ToString() {
StringBuilder sb=new StringBuilder(8);
if (b0!=0) sb.Append((char)b0);
if (b1!=0) sb.Append((char)b1);
if (b2!=0) sb.Append((char)b2);
if (b3!=0) sb.Append((char)b3);
if (b4!=0) sb.Append((char)b4);
if (b5!=0) sb.Append((char)b5);
if (b6!=0) sb.Append((char)b6);
if (b7!=0) sb.Append((char)b7);
return sb.ToString();
}
}
[StructLayout(LayoutKind.Explicit)]
public struct EF {
[FieldOffset(0)] public byte clockStop;
[FieldOffset(1)] public string8 s1;
[FieldOffset(9)] public string8 s2;
}
public override void Run(int arg) {
EF e=new EF();
e.s1=new string8("jef");
e.s2=new string8("jan");
log("names= "+e.s1+" "+e.s2);
}
This code produces the line "names= jef jan"
BTW: the ToString() method for e.s1 and e.s2 is called implicitly, due to
the string+something expression
remark: there may be easier ways to do the constructor and the ToString(), but
I cannot immediately think of one.
Hope this helps.
Luc Pattyn
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Well done
Its Great
Thank you
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Hello everybody , i just have a compression algorithm written in ansi C i need to convert it into a .dll file to add its reference into .net studio , i did that like that
new project---->c++ projects--->MFC DLL File.
and i added its files and i wrote my own methods but when i tried to incorporate it into the .net studio it refused.
so is there any way to make it a dll file and add its reference to the .net studio.
second problem:
--------------
i have A .dll file i need to extract its methods
can i use it by [DLLImport("string to the file")]
when i do that it tells me the string assigned must be constant expression , here it means constant expression not only with "const" declaration but also no variable is assigned
i did that
const string path = Application.StartUpPath+"\\compression.dll";
[DllImport(path)]
public static extern void CompressData();
but it gives me an error
Please help me how can i get these methods out from the .dll file.
Human knowledge belongs to the world.
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No, the string inside the DllImport() must be a constant, something like "kernel32.dll",
it can not be a variable.
Same is true for EntryPoint; it allows you to specify the exact name of the function
inside the DLL, but it too must be a double-quoted constant.
Luc Pattyn
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Hi,
I have created a small software using C# in .NET2003. The software contains a access mdb file as a part. How do i package my software for deployment as an installer? Thanks in advance for any link, suggestion or instructions resolving this.
Thanks
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