Re: Help Required. - C# Discussion Boards

Help with writing to buffers

28-Jul-04 11:39

This question belongs in the ASP.NET[^] forum.

- Nick Parker
My Blog | My Articles

Winter28-Jul-04 11:11

Winter

28-Jul-04 11:11

Hello all.
I have encountered some difficulties while writing a program that is supposed to use memcpy. To be honest, I can't get it to work at all, and I don't have a clue what I'm doing wrong.

Here's the most important part of the code:

<br />
DllImport("msvcrt.dll")]<br />
public static extern unsafe void memcpy(void* to, void* from, int len);<br />
<br />
[StructLayout(LayoutKind.Explicit)]<br />
private struct Buffer<br />
 {<br />
[FieldOffset(8)]<br />
public byte Buff0;<br />
[FieldOffset(0)]<br />
public int Length;<br />
FieldOffset(4)]<br />
public int Start;<br />
<br />
private static unsafe void CopyToBuffer(Buffer* buffer, byte* data, int len){<br />
if ((( buffer.Length + buffer.Start) + len) >= 262144)<br />
{<br />
throw new NullReferenceException(string.Format("Buffer overflow, or something"));<br />
      }<br />
memcpy(((&buffer.Buff0 + buffer.Start) + buffer.Length), data, len);<br />
buffer.Length += len;<br />
}<br />
}<br />

The errors I get are
"Operator '.' cannot be applied to operand of type Buffer*".
I thought that I declared buffer.Lenght as int, so why isn't it working?

I call CopyToBuffer like:

<br />
buffx = p.Finalize(); //p, being a packet<br />
unsafe {<br />
fixed (byte* buff= buffer1)<br />
{<br />
CopyToBuffer(m_Buffy, buff, buffx.Length);<br />
}<br />
}<br />
return;<br />

m_Buffy is declared as

<br />
private unsafe static Buffer* m_Buffy;<br />

and gets its value on runtime (the address of the recieve buffer).

It's a pretty simple thing, really. I just want to send a text message to a process through its recieve buffer. Smile | :)

I'm a little new to all of this, so I haven't yet fully gotten then hang of API hooking, dll injection and packet filtering and all that which migth have aided me here, but I do my best.

Any response is deeply appreciated. Rose | [Rose]

Re: Help with writing to buffers

Daniel Turini28-Jul-04 11:29

Daniel Turini

28-Jul-04 11:29

Before using memcpy (or whatever variation you may be using), I'd strongly suggest you to take a look at Marshal.Copy method.

Yes, even I am blogging now!

Help Required.

Nasir Wasim28-Jul-04 9:45

Nasir Wasim

28-Jul-04 9:45

Dear Friends
I m making Internet Club Management Software, i Want to ask 2 question's Please help me

How I can Stop / Execution of the Software ruuning on Client Machine.???

How I can Block IP/or unblock IP and banning a site on a client????

Re: Help Required.

Nick Parker28-Jul-04 10:00

How do I create a dynamic webservice client in C#

28-Jul-04 10:00

Your questions are rather vague. To answer your questions, Yes and Yes. Of course, the next logical question now from you would be 'How?'. If you could provide more information, especially about why exactly you are trying to do (beyond what you said above) we could help you. Do you have a specific programming question (i.e., something your stuck on)?

- Nick Parker
My Blog | My Articles

JM9328-Jul-04 9:41

JM93

28-Jul-04 9:41

My requirement is I need to put web service name space/ url in a properties file and invoke the corresponding web service. How can I do that ?

Here is the sample C# code which got generated with a wsdl utility using a wsdl file.
My requirement is I should read that IP addresses, Name, namesapce from a configuration file insteadof hard coding like below. Is that possible? If yes, How?

[System.Diagnostics.DebuggerStepThroughAttribute()]
[System.ComponentModel.DesignerCategoryAttribute("code")]
[System.Web.Services.WebServiceBindingAttribute(Name="MyValidationBinding", Namespace="http://33.83.76.254/")]
public class Validation : System.Web.Services.Protocols.SoapHttpClientProtocol
{

/// <remarks>
public Validation()
{
this.Url = "http://33.83.76.254:5556/soap/rpc";
}

/// <remarks>
[System.Web.Services.Protocols.SoapRpcMethodAttribute("", RequestNamespace="http://33.83.76.254/MyValidation", ResponseNamespace="http://33.83.76.254/MyValidation")]
[return: System.Xml.Serialization.SoapElementAttribute("responseXml")]
public string myvalidate(string s1, string s2)
{

Thanks,
jcm

JCM

Re: How do I create a dynamic webservice client in C#

Nick Parker28-Jul-04 9:56

Re: How do I create a dynamic webservice client in C#

28-Jul-04 9:56

Yes, you can even read it from a config file. Read the following for more details: Redirect web services at run time[^].

- Nick Parker
My Blog | My Articles

JM9329-Jul-04 8:00

JM93

29-Jul-04 8:00

Thanks Nick.

But I need to build that as DLL. If I build the DLL how do I deploy the config file with the DLL. Where should we put the config file?

Also, the link talks about only in the constrcutor of the program like below

public Books() {
this.Url = ConfigurationSettings.AppSettings["WebServicesUrl"]
}

but how do we replace the name, namespace values before the method call like below

[System.Web.Services.Protocols.SoapRpcMethodAttribute("", RequestNamespace="http://33.83.76.254/MyValidation", ResponseNamespace="http://33.83.76.254/MyValidation")]
[return: System.Xml.Serialization.SoapElementAttribute("responseXml")]
public string myvalidate(string s1, string s2)
{

Thanks,
JMC

Re: How do I create a dynamic webservice client in C#

Nick Parker29-Jul-04 8:45

How do I disconnect my crystal report from it's datasource

29-Jul-04 8:45

The code you are looking at is simply a proxy that was generated from wsdl pointing to your web service. The proxy is what talks to the web service and returns the values to you. You can deply the config file right along with your assembly, within the same directory. The problem is that attributes must be a connstant expression, in other words you can't set thier values by an inline method call or in your case, pointing to the AppSettings to gain dynamic values at runtime. If you read through the comments in that link I sent you, Peter Cook suggest that you set the web reference to dynamic rather than static thus allowing Visual Studio .NET to handle this for you.

- Nick Parker
My Blog | My Articles

WMI Windows Service

silverbullet28-Jul-04 9:12

silverbullet

28-Jul-04 9:12

Hi, I need to check the status of WMI services (running, stopped, or disabled) on a local computer, using System.Management classes in .NET. If anyone knows please update this.

Thank you.

Thank you
Silver Bullet

Re: WMI Windows Service

Heath Stewart28-Jul-04 10:10

Heath Stewart

28-Jul-04 10:10

If WMI isn't running, you can't use WMI to check the status of itself. The best way is to use the ServiceController like so:

ServiceController sc = new ServiceController("winmgmt");
if (sc.Status != ServiceControllerStatus.Running)
  sc.Start();

Microsoft MVP, Visual C#
My Articles

kornstyle28-Jul-04 8:24

kornstyle

28-Jul-04 8:24

I have made a report using crystal reports.net. I am using a MDB file as my datasource. When I close the form that displays my report, the report is not disconnecting from the datasource. What do I need to do to disconnect the report from it's datasource.

Thanks.

Re: How do I disconnect my crystal report from it's datasource

Heath Stewart28-Jul-04 8:50

Heath Stewart

28-Jul-04 8:50

Use a DataSet as the data source. Fill your DataSet with what you need from the Jet database (MDB) and pass it to SetDataSource. In the Cyrstal Reports designer, you can bind against a DataSet but it helps to use a typed DataSet, which xsd.exe or the DataSet designer in VS.NET can do easily.

If you have a view, table, or tables that you want to fill the DataSet with, connect the Jet database in the Server Explorer, browse to the view or table(s), and drag and drop them into a new DataSet item you can add to your project. This will create the necessary elements for you.

Then in the Crystal Reports designer, you can add a reference to that typed DataSet and design your report as you would normally.

This makes for a good disconnected architecture since it doesn't matter from where that data is obtained (could be a Jet database, SQL Server, Oracle, an XML file, etc.).

Microsoft MVP, Visual C#
My Articles

logg/scan open windows

pat27088128-Jul-04 6:25

28-Jul-04 6:25

hi,

does anybody know how i can scan and/or log in a file, that e.g. for all 5 seconds or when a window opens, it would be logged in a file, which windows are opened?(the title of the window or something else) i need this mechanism for usability tests.

i hope someone can help me.

thanks in advance

yours sincerely

patrick

pat27088128-Jul-04 6:55

28-Jul-04 6:55

i know can also be not a C# specific question but it anybody knows a solution with c# it would be c#-specific. the best case were if anybody know a tool with which i can solve the quoted problem??

thanks in advance.

patrick

Heath Stewart28-Jul-04 7:04

Heath Stewart

28-Jul-04 7:04

Enumerating the top-level windows is easy: P/Invoke the EnumWindows native API:

[DllImport("user32.dll")]
private static extern bool EnumWindows(EnumWindowsProc proc, IntPtr lParam);
 
private delegate bool EnumWindowsProc(IntPtr hWnd, IntPtr lParam);
 
[DllImport("user32.dll", CharSet=CharSet.Auto)]
private static extern IntPtr GetWindowText(IntPtr hWnd,
  [Out] string title, IntPtr maxCount);
 
public void EnumWindows()
{
  EnumWindows(new EnumWindowsProc(Callback), IntPtr.Zero);
}
private bool Callback(IntPtr hWnd, IntPtr lParam)
{
  string title = new string('\0', 260);
  if (GetWindowText(hWnd, title, 260) != IntPtr.Zero)
    Log(string.Format("{0:x8}: {1}", hWnd, title);
}

If instead of windows you want to enumerate all running processes (and perhaps filter those that do not have application windows), you can use Process.GetProcesses and, optionally, check if Process.MainWindowHandle is IntPtr.Zero (not graphical).

Responding when a window opens is a bit more tricky. You must efficiently implement a Windows hook and handle the WH_CBT (0x05) message. This message is documented in the Platform SDK along with related APIs like SetWindowsHookEx. The callback (CBTProc) is called whenever a window is about to be activated, created, destroyed, minimized, maximized, moved, or resized (so you'll need to filter these appropriately based on your needs).

You can read more about implementing windows hooks in .NET (using the C# language) by reading Using Hooks from C#[^] here on this site. Any questions specific to this article should be directed to the article's message board at the bottom of the page.

Microsoft MVP, Visual C#
My Articles

pat27088128-Jul-04 7:41

28-Jul-04 7:41

hello,

thank you for your reply, unfortunately i do not really know what you mean with your solution, although i thought i have good experience in c#, ado.net, asp.net, etc.

the situation is as follows: i want to log the events on a PDA (DELL AXIM X30 Windows Mobile 2003, Second Edition, .NET Compact Framework), like when a user makes an entry in the time planner,..etc. So it should be recorded if a window opens, respectively what window opens, etc.

is this possible with your idea? - and can you probably explain me your solution in a simpler way? Sigh | :sigh:

i also read the article "Using hooks from c#" but i do also not look through it.

i hope you can help me once more, because i would need this for a Thesis (diploma).

thanks in advance.

yours sincerely

patrick

Nick Parker28-Jul-04 8:11

28-Jul-04 8:11

The EnumWindows function is a native function in Windows, you must P/Invoke it in order to call it directly in managed code. What exactly don't you understand about Heath's response, it's seems rather clear to me but if you could be more specific we would be able to help you. What he suggested will work, however I would recommend you read further about Windows hooks so you can understand the concept trying to be relayed here.

- Nick Parker
My Blog | My Articles

pat27088128-Jul-04 8:23

28-Jul-04 8:23

hello,

yes i also think it should be better when i read further about windows hooks. do you know some good literature? and when this solution also works on a PDA this would be outstandig!! - because i search for a long time for a solution for that problem.

what do you mean with P/Invoke? - Can I take over otherwise the code in that way?

yours sincerely

patrick

Nick Parker28-Jul-04 8:33

28-Jul-04 8:33

One of the best articles I have seen is Win32 Hooks[^], however there are other articles on CP that cover this as well, do a search and read them all to get a good feel for the subject. P/Invoke is described with an example here[^].

- Nick Parker
My Blog | My Articles

pat27088128-Jul-04 11:25

28-Jul-04 11:25

Hello,

Thank you for the references and i already read the articles and i try to reflect my thoughts - i hope they are right?

With the P/Invoke - the DLLImport i can change methods of a Dll-File, but do i need this mechanism when i use hooks? - i don't think so.

With Windows Hooks the events will be recognized before they will be executed in the application and so can be logged.

I think for my problem i need the WH_CBT Hook and the HCBT_ACTIVATE,
HCBT_CREATEWND, HCBT_DESTROYWND, HCBT_MINMAX, HCBT_MOVESIZE, HCBT_SYSCOMMAND.

With these hooks i can log when a window opens (whereby i do not exactly know the difference between activate and createwnd), a window closes, a window minimizes or maximises and when a command executes.

But now if my thoughts are right i miss the practical relation to the c# and how i can implement that.

i hope you can give me further help. Sigh | :sigh:

thanks in advance.

yours sincerely,

patrick

PS: I hope you know that it still concern the event logging of the PDA, where Windows Mobile 2003, Second Edition and the .NET Compact Framework is installed. I thought this method with logging the open windows and so on is the best way to know what the user do with the PDA, because that is what i want to know and this should be logged in any wise.

pat27088128-Jul-04 23:01