PrnAdmin.Ports Converting __ComObject To PrnAdmin.Port
Nov 6, 2008
I have written several classes that use System.Reflection to create xml serializable classes. I am currently working on on enumerating printer objects using PrnAdmin.dll. The PrnAdmin.Ports method returns as an object. When I enumerate through the ports I use the following code
Code:
Dim _Master as New PrnAdmin.PrintMaster
For each _Port as PrnAdmin.Port in _Master.Ports(ServerName)
[code]...
While debugging I put my mouse Over the _Port variable and it is represented as System.__ComObject instead of PrnAdmin.Port. Even when I use _Port as an Object and try to use CType to convert it to a PrnAdmin.Port it is still shown as a System.__ComObject.
My question is... How can I get the underlying type of a __System.ComObject so that I can expose PropertyInfo and MethodInfo members?
I'm learning the serial port programming. So, I study the code samples from MSDN - VB101SamplesBCL2 http:[url].....While ran the solution of "UsingTheSerialPort", It shows error: It highlights one sentence textBox2.Text = SerialPort1.ReadLine() -- Line 40 ,and says :
"InvalidOperationException was unhandled - Cross-thread operation not valid: Control 'textBox2' accessed from a thread other than the thread it was created on."
I was wondering if its possible for VB to display all available COM ports that are open. he reason that I ask this is because this program will be run on various computers where the COM port will not always be the same. I have a text box now that the user can choose which com number he/she wants but if the wrong one is entered, the program crashes rather than displaying an error message. It would also be nice for the system to show which available com numbers there are
I've been given this simple VB application and library which I'm told can open a door/turnstyle attached to the printer port at 0x378 base address.'Inp and Out declarations for port I/O using inpout32.dll.
Public Declare Function Inp Lib "inpout32.dll" Alias "Inp32" _ (ByVal PortAddress As Integer) _ As Integer
[code]....
how to declare the library functions and what to declare the variables as (&H378 is obviously not an integer)
I am using a VB.NET(VS2010) to read data from serial port. I have 8-bit data to collect through rs232. This data is represented numbers. What reading method should I use and how to convert it to double format?
I'm new to VB, I'm now want to know how to convert received string to double. I'm receiving string like this 420.8 280.9 140.2 from serial port.. and transferred it into textbox.. I'm using following code to split string and to convert to double
I have been working with System.reflection namespace and i have problems to get value of properties in system.__ComObjectMy objective is:obtain a collectionfor each object in collection get the propertie (example ID)
I am trying to create an Excel file using reflection. The reason, the application will be running on many machines some of which may or not have excel installed. I decided to embed the "Microsoft.Office.Interop.Excel.dll" and via reflection generated the excel spreadsheet. The code I am trying to resemble is:
Unable to cast COM object of type 'System.__ComObject' to class type 'rjsDocMan.Folder'.Instances of types that represent COM components cannot be cast to types that do not represent COM components; however they can be cast to interfaces as long as the underlying COM component supports QueryInterface calls for the IID of the interface.The code where it is flagging the error is:
I am building a software which will be used to create a remote desktop connection. However I'm getting this error:
Unable to cast COM object of type 'System.__ComObject' to interface type 'MSTSCLib.IMsTscNonScriptable'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{C1E6743A-41C1-4A74-832A-0DD06C1C7A0E}' failed due to the following error: Δεν υποστηρίζεται τέτοια διασύνδεση (Exception from HRESULT: 0x80004002 E_NOINTERFACE)).
I have a Windows form.in windows form have a combo box that give me a list of available port serial with it code (Dim ports As String() =SerialPort.GetPortNames())for example( Com1,Com8,Com15,...).but I want to give me fullname of serial port in device manager for example in dvice manager is these (Comunication Port(COM1) - Printer Port(LPT1) And USB Serial Port(COM8)).how to Get it?
Code: Dim dom As New DOMDocument30 dom.async = False dom.Load(serverAddress & "/App/filelist.jsp?type=content") For i = 0 To dom.childNodes.item(1).childNodes.length - 1 downloadfile(dom.childNodes.item(i), mcount, currentpath) Next
The above code is activated upon clicking of a button. i have the server address declared. and using the domdoc to load the jsp file to generate the xml data. and using for loop, i call the download file function which accepts the following parameters
Code:Public Sub downloadfile(ByVal domdoc As Xml.XmlNode, ByVal totalcount As Integer, ByVal currentpath As String)
The totalcount and currentpath work fine, but when i pass in the dom.childNodes.item(i) , error pops up.
--------------------error message------------------------------------------Unable to cast COM object of type 'System.__ComObject' to class type 'System.Xml.XmlNode'. Instances of types that represent COM components cannot be cast to types that do not represent COM components; however they can be cast to interfaces as long as the underlying COM component supports QueryInterface calls for the IID of the interface.-------------------------------------------------------------------------------
If I uninstall the COM1 and reboot, it works. If I shut down (power off) and restart, I get the message below. If I uninstall then click on Scan for Hardware Changes,The given port name does not start with COM/com or does not resolve to a valid serial port. Parameter name:portName
I am trying to get my 4 port USB relay board to work in VB.net using the COM PORT. I found some code from a poster who has the 16 port USB relay version. When trying his code i can only get it to turn on relays 1-3 all at the same time. The product can be found here: USB 4 port relay
"01+//" - Relay 1 is switched ON "01-//" - Relay 1 is switched OFF "02+//" - Relay 2 is switched ON "02-//" - Relay 2 is switched OFF
[code].....
So i am confused as to how to separate each relay out with that code above and just be able to turn on any number 1-4 relay on or off independently from each other!
Anyone here has an idea where I can get the ports name listed in my PC? [code]I could get COM26 and etc. if any, but that's not what I want. Instead of retrieving COM26, I want USB-SERIAL CH340 or USB-SERIAL CH340 (COM26). How could I do that?
I will explain first what kind of program we are talking about: The program that I made works togehter with my PIC Microcontroller to control 2 stepper motors. One for the rotating motion and the second for a tilting motion. With this system I want to make a airplaine pointing and tracking system.
What is the best way of communicating with Serial ports and TCP/IP communcation using vb.net?Using visual studio .net can we make it easier?? Can anyone send me sample application of communications?If I write a program communicating with my hardware using Searial port or TCP/IP, will the program be slow?? Are there any programming techniques working with communication ports?
We need to put a firewall in between our servers and a couple of clients. To do this we need to limit the number DCOM ports available so that we know what ports to open on the firewall.The question I have is do we need to limit the number of ports on all the machines inside the firewall as well as outside. This would cause an issue as we have lots of machines which would need to be modified.If DCOM has the intelligence to negotiate on port 135 which port is available on both machines which need to communicate, we will only need to modify the 2 machines on the outside of the firewall.
I am creating a USB "cookie dispenser" (long story) and I plan on programming it by, when cookie.exe starts, it disables the port, you plug the USB in and press a button and it enables the port (thus powering the device). What I need to know is, is this at all possible? And if so, can you help me get it to work? I know I should put in an effort but it's late for me (UK) and I want to post this overnight so that you guys (in the USA may
I am trying load a text file that contains ips and ports in the format of Ip:Port this is the code i have so far...its gives me an error of.... Is operator does not accept operands of type 'Boolean'. Operands must be reference or nullable types.
I Need to be able to read an unknown number of serial ports (I plan to limit the number to 10). I'd like to use a datareceived handeler for all of them. This is what I came up with, that seems to work with my test ports. However I'm wondering if thiscould cause any problems if more data is received than I'm currently testing with. It is possible that one or two ports will be transmitting 16 records per second each. Here is the code I'm testing with:
I want to experiment with COM ports but I'm stuck trying to figure out the COM port on my laptop. When I run the following program:
[code]...
PCI expansion card with my wireless internet card in there the hp manuals also say that my laptop should have a PS/2 mouse or keyboard slot but i dont see it anywhere. what ports could "COM3" be refering to?
I want to get the details of a com port on my machine. To be more precise the com port presents itself in the device manager as: MyPort(COM3) I know how to get the name of the port i.e. COM3. Is there a way to get the rest of its description i.e. "MyPort".
