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WinForms app displays differently on different computers.

3-Feb-04 11:15

If you're using the Windows Installer project in VS.NET, add the output of your project to the installer and it is updated whenever you recompile your C# project (it becomes a dependency of the installer project).

I'm not saying the GAC doesn't work, I'm just saying that it can lead to problems until you're done testing. You've already had one. If you use automatic versioning you'll have lots of assemblies (differing only by version) in your GAC. It doesn't hurt anything, but it sure clutters up the GAC. It's just a recommendation that's not uncommon when debugging applications, especially in larger teams.

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~michL~2-Feb-04 12:47

~michL~

2-Feb-04 12:47

I have a WinForm application which appears fine on my computer and several others, but I have found one computer on which some of the controls appears "cut-off".

I have all the controls on the application anchored so that when i view the application on my computer, it looks fine no matter how I resize it. It seems as though on this one other computer that the form is not following the anchoring I had set up. The strange part is, that this only happens on one tab of the application. (There are several other pages in the TabControl set up in the same manner which display fine on all computers). Also, when this "problem computer" is used to view the application via RAdmin on another computer, it appears as it is supposed to.

Any ideas on what could be going on here???

Re: WinForms app displays differently on different computers.

Heath Stewart3-Feb-04 5:29

Re: WinForms app displays differently on different computers.

3-Feb-04 5:29

~michL~ wrote:
Any ideas on what could be going on here???

Screen resolution.

Since .NET uses pixels and pixels display differently on different resolutions, the layout of the form can't truly be garaunteed. This is why some languages like VB6 (and below) use twips, points, and other logical units. The anchoring won't matter in this case because the initial positions and sizes of the controls are correct in relation to pixels. It's pretty hard to explain.

I've actually never seen that big of a problem before. What resolution are you using? What resolution is the other machine using?

If necessary, you can always P/Invoke the GetDeviceCaps native function (for which the SystemInformationClass does, but doesn't support everything) and get the number of pixels per whatever logical unit you like. The reason it works when you use RDP (termainal services) is because you can specify a resolution in which to work when you connect. The graphics card on the target machine should support your target resolution, so you might want to try using that resolution locally on that machine.

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~michL~3-Feb-04 13:44

~michL~

3-Feb-04 13:44

Unfortunately, all resolutions on that particular computer display incorrectly so it could not be fixed that easily...meanwhile, on other computers all resolutions do display correctly. I had been using 1280x1024, while the other computer had a res of 1024x768, but like I said, even when changing the resolution of the other computer to 1280x1024, the problem was not fixed.

And since the resolution doesn't solve the problem, it seems that GetDeviceCaps would not solve it either.

Re: WinForms app displays differently on different computers.

Heath Stewart3-Feb-04 17:54

Programatically iterating through controls in C# csharp or VB.net

3-Feb-04 17:54

There's more to calculating pixels per logical unit. What is the dpi of the monitor? Is the right driver configured for the display adapter and the monitor itself? These all have a major impact on how things are displayed on your monitor. There's plenty of information about this in the Platform SDK.

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billoo2-Feb-04 11:51

billoo

2-Feb-04 11:51

I have a Windows form in which I have 5 Button controls, named B1, B2,
B3 .... B5. I want to programatically iterate through these controls,
where I have to work on their properties. Initially all Buttons need
to be invisible. But then iteratively, I want them to be visible. A long handed version is as follows:

while (dr.Read()) {
B1.Visible=true;
B2.Visible=true;
B3.Visible=true;
B4.Visible=true;
B5.Visible=true;
}

I want the following:

while (dr.Read()) {
int i=1;
Bi.Visible=true; //this is just my intent, not an actual statement
i=i+1;
}

where dr is a SqlDataReader. I want i to iterate from 1 through 5, and
then all Buttons are visible. I tried concatenating string to form B1,
B2 etc. programatically, but that does not work.

Help appreciated.

Re: Programatically iterating through controls in C# csharp or VB.net

Heath Stewart2-Feb-04 12:05

Re: Programatically iterating through controls in C# csharp or VB.net

2-Feb-04 12:05

There are many ways you can do this, such as keeping an array or collection of specific controls you're interested in, or checking the type of the Control in the Controls property of the container Control (like a Form, UserControl, Panel, etc.) like so:

foreach (Control c in Controls)
{
  if (c is Button)
  {
    Button b = (Button)c;
    b.Visible = true;
  }
}

If you only want specific names, make sure the Name property of the Button is assigned and compare that with "B1" through "B5" to make sure it's a Button you want to control.

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billoo2-Feb-04 12:33

billoo

2-Feb-04 12:33

Heath and Collin, thanks for the reply.

One of the issue is that I am trying to generate a switchboard menu. I have a total of 15 buttons. As users click on the items in the switchboard, the number of buttons dynamically grow or shrink depending on the sub-items under the item being clicked. So, I do not have a static number of buttons that I need to work with.

For example the main menu may look like this:

* Main
* InventoryControl
* ProductionControl
* Exit

This will be represented by 4 buttons (where * represents a button) with corresponding text.

If a user clicks InventoryControl, this window form will be repainted with a different menu, which may have 10 items. So, then I have to make those 10 buttons visible.

Thanks for the help

Re: Programatically iterating through controls in C# csharp or VB.net

Colin Angus Mackay2-Feb-04 12:06

Colin Angus Mackay

2-Feb-04 12:06

Two ways:

1) You could add all the buttons to a collection then iterate over the collection.

2) Alternatively, if these are the only buttons on your form then you could just iterate over the existing Controls collection. (You will notice in the "Windows Form Designer generated code" section there is a section that has lots of this.Controls.Add(...);

Example using existing controls collection on the form:

Button btn;
foreach(Control ctrl in this.Controls)
{
    btn = ctrl as Button;
    if(btn == null) // Not a button
        continue;
    btn.Visible=true;
}

--Colin Mackay--

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"You can have everything in life you want if you will just help enough other people get what they want." --Zig Ziglar

Updating table from datatable

zuhx2-Feb-04 11:38

zuhx

2-Feb-04 11:38

I am trying to update a table from a datatable. The datatable is populated first from a text file and then I would like to get that data into a database datatable. However the code below does not work, part of it is I do not know how to associate the connection string to the data adapter. Also, is there anything else I need to do? Do I need to have separate Update, Insert, and Delete commands or is it possible to just call the Update command?

ConnectToDb connection = new ConnectToDb().conn; //this returns a SqlConnection
SqlDataAdapter da = new SqlDataAdapter();
da.Update(ds.Tables["TradeOrderFillsPre"]);

Re: Updating table from datatable

Heath Stewart2-Feb-04 12:01

2-Feb-04 12:01

Reading the table into a DataTable and adding that to a DataSetis what I would recommend, but iterating over the list of values in the text file and using a simple SqlCommand with SqlParameters (so you declare the command one and parameterize it to simply change the values and call ExecuteNonQuery) would also be easy and more efficient.

If you want to use the SqlDataAdapter, you must at least have the SelectCommand assigned to with a SqlCommand for your SELECT statement. In order to insert, update, or delete rows, however, you must have the InsertCommand, UpdateCommand, and DeleteCommand assigned on the SqlDataAdapter. You can use the SqlCommandBuilder with the SelectCommand if the command is simple enough (i.e., JOINs and other advanced statements are not supported). Also, the SelectCommand must be parameterized (see the SqlCommand.Parameters property).

See the SqlDataAdapter class documentation in the .NET Framework SDK (installed by default with VS.NET, and available online from http://msdn.microsoft.com/netframework[^]) for more information and an example of how to use some of these classes.

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ListView

Gary Kirkham2-Feb-04 11:23

Gary Kirkham

2-Feb-04 11:23

I have a list view with 3 subitems. I am handling the mouse down event and I would like to find out which subitem was clicked. I can find no easy way to get the subitem rectangle.

How do I do this?

Gary Kirkham

A working Program is one that has only unobserved bugs

I thought I wanted a career, turns out I just wanted paychecks

Re: ListView

Heath Stewart2-Feb-04 11:57

2-Feb-04 11:57

One way is to use ListView.GetItemAt to get the ListViewItem that was clicked, then enumerate the ListView.Columns collection and compare the x-coordinate with the incremental ColumnHeader.Width property (i.e., incrementally add the width of the ColumnHeaders as you enumerate and see if the x-coordinate falls within the start and end x-coordinates of the column.

Another way is to override WndProc in a derivative class, define the NMITEMACTIVATE structure, and use the iItem and iSubItem members of the struct. For more information, see the Platform SDK for the LVN_CLICK notification message and the NMITEMACTIVATE structure (includes the NMHDR structure, which you can simply merge the members of into the NMITEMACTIVATE struct if you don't plan on using the NMHDR struct elsewhere).

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Re: ListView

Gary Kirkham2-Feb-04 12:02

Gary Kirkham

2-Feb-04 12:02

Thanks for the reply.

Heath Stewart wrote:
compare the x-coordinate with the incremental ColumnHeader.Width property (i.e., incrementally add the width of the ColumnHeaders as you enumerate and see if the x-coordinate falls within the start and end x-coordinates of the column.

I thought of that, but it just seemed so kludgey Smile | :)

Gary Kirkham

A working Program is one that has only unobserved bugs

I thought I wanted a career, turns out I just wanted paychecks

Re: ListView

Heath Stewart2-Feb-04 12:06

2-Feb-04 12:06

Yeah, but it's certainly a heck of a lot easier than the second way (which encapsulates notification messages and structures for the List-View common control like most of the controls in the .NET Framework base class library do)! Smile | :)

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Good PDF Viewer control?

Alex Korchemniy2-Feb-04 11:04

Alex Korchemniy

2-Feb-04 11:04

I ran into some serious bugs in the adobe reader 6.0 activex control. (pdf.ocx has problems when trying to load .xfdf file) I've been at Adobes forums and posted about this topic. People say that the control has zero support. What is a good pdf viewer control that has support for .xfdf ?

(auto merge with linked pdf and no need to save the result. Just needs to have basic viewing features and has to be able to print)

COM/C# datatype mismatch

KingTermite2-Feb-04 10:26

2-Feb-04 10:26

I have a C# com object that I'm creating which I'm testing in a VB environment. This COM object is also calling other COM objects which were written in VB.

I have a VB COM object with a method who's signature looks like this:
Public Function MyFunction(varNames() As String) As String()

I'm trying to send in a string array when calling this guy in my C# code like this:

string[] sNames = { "ProjectName" }; // 1 element array<br />
COMInt.ComClass oCDS = new COMInt.ComClass();<br />
<br />
sValues = oCDS.MyFunction(ref sNames);

I get type mismatch on the "ref sNames". This is just one of many combinations I've tried, but have not quite figured out the correct type match.

Here is the error I receive in VS.Net:
D:\CSS\Dev\ProjName\ProjClass.cs(255): The best overloaded method match for 'COMInt.ComClass.MyFunction(ref System.Array)' has some invalid arguments

Can anybody help me out and explain this?

P.S. Sorry for all the "MyFunction" and "ProjClass", etc.... but this is at work and I could get in trouble just for posting the names of things (they are VERY picky).

There are only 10 types of people in this world....those that understand binary, and those that do not.

Heath Stewart2-Feb-04 10:29

2-Feb-04 10:29

Check the signature of MyFunction. If it doesn't have a ref or out keyword before the param, don't use either ref or out to call the method. Strings in .NET (as well as most other classes) are already reference Types, so you rarely need to use ref or out (sometimes it's necessary, like for pointers to pointers, but it's typically only necessary for value types).

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KingTermite2-Feb-04 10:59

2-Feb-04 10:59

Yeah, I know what you're saying. The signature was the first code section/line.

I tried it first without the ref, assuming that was the correct way (most of my experience being a C programmer).

That just gave me the same error. This one shows up too:
D:\CSS\Dev\ProjName\ClassName.cs(255): Argument '1': cannot convert from 'string[]' to 'ref System.Array'.

BTW...also to note, the new C# must match the existing VB signature because that is a long time used COM object so interface can't change.

There are only 10 types of people in this world....those that understand binary, and those that do not.

Heath Stewart2-Feb-04 11:01

2-Feb-04 11:01

No, what was the signature in the CCW (the interop assembly) that was generated from the VB COM object? Did it use a ref? The original error message you got indicates that it does not.

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KingTermite2-Feb-04 11:09

2-Feb-04 11:09

Oh...sorry..I got ya now. And no, it didn't use ref, I didn't think it did. I was only trying that after it didn't work originally without the ref thinking maybe I needed that to send it in.

This is the interop assembly (the type lib you mean I hope...this is my first taste in COM).

SAFEARRAY(BSTR) MyFunction([in, out] SAFEARRAY(BSTR)* varNames);

There are only 10 types of people in this world....those that understand binary, and those that do not.

Heath Stewart2-Feb-04 11:14

2-Feb-04 11:14

No, the assembly generated after running tlbimp.exe on the typelib, or using VS.NET to do the same. Judging by the method declaration, though, you should end up with something like the following:

void MyFunction(
  [MarshalAs(UnmanagedType.SafeArray, SafeArraySubType=VarEnum.VT_BSTR)]
    string[] varNames,
  [MarshalAs(UnmanagedType.SafeArray, SafeArraySubType=VarEnum.VT_BSTR), Out]
    string[] retVal);

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KingTermite2-Feb-04 11:40