Restrict input to a specific device in C# - c#

I have two devices(KeyBoard and BarCodeScanner) and 2 textboxes(text box 1 and text box 2).
Now I want to restrict user that he can only use keyboard in text box 1 and barcodescanner in text box 2.
How is this possible in C#?

You should have a look at this: Read data from Bar Code Scanner in .net (C#) windows application!
So your scanner might send special characters to help you identify it the input was from a scanner, or maybe it provides you with an additional library you could use to detect such events.
Let's suppose thought the scanner acts identically to a keyboard without any special characters to help you know it was from a scanner and without any additional library from the manufacturer site you could use.
Then what you could use is: measure the typing speed in the KeyDown event of the second textbox.
I suspect the scanner enters the code instantly so you would have a huge typing speed measured.
Then if the typing speed is greater than a threshold ( E.g. for humans the world speed record is somewhere around 1000 characters per minute) then you delete the text that was entered.
It's hacky, but I've got no better idea.

I worked with barcode scanner only once. In my scaner was possible to force it to generate special control sequence before it pass input to computer. This behavour was mastered through scanner's native software. But I cant specify any details because of I didnt participate in customizing - my colleague customized it before me .
In my case scanner sent Ctrl+J before scanned date and I was able to determin from which source input come from keyboard or from barcode scanner.

It depends on how the scanner is connected I guess. If it's just wired in between the computer and the keyboard, you're out of luck, since there wouldn't be any reliable way to distinguish keyboard inputs from scanner inputs.
If it's connected separately there must be some means to get at the scanner data, maybe by way of a class that the scanner software provides, so you have to use what's provided there and put whatever you receive into TextBox2.Text. As for disabling the Keyboard input for this box, you could simply prevent any input by setting TextBox2.ReadOnly = true.

Related

C# Barcode scanner

I am currently writing a program where I wish to use a barcode scanner to scan a bar code into a system, then use this information to make certain decisions.
How can I get C# to react when I use the bar code scanner? Do I need certain DLLs or APIs to use a bar code reader? I can create bar codes but need a way for C# to read them externally and import them into the program.
Richard,
It is important to know that typically barcode scanners support multiple interfaces that fall into two categories. Many have an option that makes the barcode scanner appear as a keyboard and whenever you scan data the text is entered into your application at the insertion point. The manufacturer of the scanner may refer to this as Keyboard, Keyboard Wedge, HID Keyboard or simply HID mode, however the last one in this list is technically not accurate as there are other HID interfaces besides keyboard.
The second category is often referred to as application mode. There are several different interfaces that support application mode, such as IBM Scanner, HID POS Scanner, etc. Each of these interfaces represent follow a specific hardware specification. You must make sure that the mode that your scanner is in matches the SDK that you are using to interact with the scanner.
If you are using .NET Framework, you may find POS for .NET useful as it abstracts the barcodes scanner away from the software in a way that allows you to use scanners from multiple manufacturers without changes in your application. In this case, you will need to acquire an OPOS Service Object from the scanner manufacturer to use with POS for .NET. See POS for .NET 1.14.1 Download page for more information: https://www.microsoft.com/en-us/download/details.aspx?id=55758
Terry Warwick
Microsoft
As far as it is connected to your device correctly , it will automatically pass data to your Focused itembox in your program.so if you run your program.exe which has a textbox, when you scan a barcode , it will be parsed into that textbox (it has to be focused).
Use the class SerialPort. It can listen your ports and then when you will use your scan the program will read it.
while (spPort.BytesToRead > 0)
{
carac = (char)spPort.ReadByte();
if (carac != 08)
m_mystring += carac;
}
Here is an example of how you can read it. And this is the link to the class : https://msdn.microsoft.com/en-us/library/system.io.ports.serialport(v=vs.110).aspx
It also depends on what form your application takes. If you have the option of uploading a picture or accessing the camera, you can pull an image into your code and then use one of many SDK's to read the barcode out of the image.
I have just implemented this using a web application, and I used the ZXing SDK, which is a free port to .Net and is available via NuGet.
https://github.com/micjahn/ZXing.Net
If you're just starting out, samples within SDKs are the best place to get started.
UWP apps to handle barcode are best explained in the universal samples at --> https://github.com/microsoft/Windows-universal-samples/tree/master/Samples/BarcodeScanner
A Win32 C# .net sample can be found in the Pos For .Net 1.14 SDK mentioned earlier.
Most barcode scanners are "HID" devices, which means that they write the data of the barcode (the small numbers) like you would do manually with your keyboard, they're also recognized as a keyboard by most operating systems.
So the easiest way is just having a textbox. Make sure the focus is automatically on the textbox before the scan, and if you want it to automatically do something, make sure to have an event listening for an enter keydown. (Most HID scanners press an enter right after the scan is complete.)
Barcode scanner has are sending keys when they detects Barcode same goes with QR Scanners.
All you need is just put the focus in a textbox and use some events like text change or keypress/keydown since most of the scanners has an option for you to add/remove newline at the end of each set of keys it returns.
Using a physical barcode scanner is one option, but you're limited to scanning one barcode at a time.
An alternative option would be passing multiple documents, either as images or PDFs, to your application to process in bulk.
IronBarcode is a c# barcode scanner that also allows you to read barcodes quickly and accurately in this way.
// The BarcodeResult.ReadBarcodesMultiThreaded method allows for faster barcode scanning of multiple images or PDFs.
// All threads are automatically managed by IronBarCode.
var ListOfDocuments = new[] { "Image1.PNG", "image2.JPG", "image3.PDF" };
PagedBarcodeResult[] BatchResults =
BarcodeReader.ReadBarcodesMultiThreaded(ListOfDocuments);
Disclaimer: I work for Iron Software.

WinCE device - change keyboard input method

We have a Casio DT-X8 scanners that we are using in our company. They run .NET Framework 3.5 and WindowsCE 5.0
I have developed an app for them to suit our needs. The keypad on those scanners is the old mobile phone style, so a number 2 would be the number 2 but also ABC and abc. You switch between modes using the F8 button on the scanner. We have textboxes in the application that requires either a text input or a number input. It is sometimes time consuming to switch between the modes using the F8.
My question is, is there a way to set the input method through the app? I am already using the core.dll file to set the correct date and time on the scanner, so is it also possible to do similar with the input method?
I have searched google and stackoverlow but couldn't find anything that relates to my question. Many problems were to do with controlling the language input, but not the actual input type.
I am not looking for a complete code as that I can do myself. I just need some directions as to what to look for and how to tackle it.
I think that this feature is specific for that device.
Windows CE provides a way to change the software keyboard (look for Software Input Panel or SIP in the documentation), but does not apply to HW keyboards.
Do you have any "companion" app that can do this? If you have you know, at least, that it's possible to do it in SW.
If the HW manufacturer provides his own SDK that would be the first place where I would check for such a feature.
You may also have a look at the keybd_gen API in CE, this can be used to generate an emulated pressure of the F8 key. But I'm not too confident that this will work, since the key may be managed inside the keybd driver or at a lever lower than the one affected by that API and, in any case, it may be tricky to keep track of the keyboard state if the user presses that key when not running your app.

Control to allow barcode scanner input, but ignore keyboard input [duplicate]

I have made a Windows Form application with a textbox. I will force users to use the barcode scanner, so the keyboard input should be disabled. The KeyPressed event does not work, because is also disabled input from the barcode scanner.
I thought maybe I can set a timer on the TextChanged event, but I do not really know how it works.
Have someone a good idea?
Based on your description, I assume that your barcode scanner is an HID barcode scanner. If so, there is no easy answer here because the barcode scanner functions exactly like a keyboard. Disabling keyboard input will disable the barcode scanner.
I have done this before, and there are a few solutions I know of:
Use a barcode scanner that is not an HID barcode scanner. Ex: Serial, or something like that.
Configure the barcode scanner to send a special character at the start and end of the barcode scan. (This is something you can do if you have the manual for the particular model of barcode scanner.) Write your KeyPressed event to listen for these special characters as a signal that it is getting data from the barcode scanner. When it sees them, enable and disable the text box.
Use Windows API calls to communicate directly with the barcode scanner. This requires knowing the VID and PID of the barcode scanner, and some detailed knowledge of APIs like GetRawInputDeviceInfo, GetRawInputData, and RegisterRawInputDevices. This is very powerful, since you can receive barcode input from anywhere in the application, but it is very complex.
However, one caveat: You probably don't want to disable the text box at all. What if the barcode is damaged and the scanner cannot read it? You always want the user to be able to manually enter the barcode. Next time you go through the cash register at a store, notice that there is always a way to manually enter the barcode.
You can find the way to check with keysUp and Keysdown event.
Check here for detailed answer.
Check here for answer
Check here for github code

How do I correctly capture data from a Symbol LS2208 barcode scanner with C#

I have been asked to develop a C# Winforms application that reads barcodes and processes data based on products with the relevant barcode.
The barcode scanner we're using is a Symbol LS2208 usb scanner and when it came there was no instructions or cd in the box. We plugged it in, it beeped at us and were were able to scan barcode values into notepad as a test.
In my application, how do I ensure that the scanner populates data into the relevant textbox (I've been setting focus after every other action such as button clicks etc) and how do I know when the entire barcode has been scanned? Currently I have a form timer that ticks every 50ms and checks the length of the textbox value. If it stops getting bigger, I assume the entire barcode has been written.
It just feels a bit "clunky" and wondered if there was another way to do this?
Distinguishing Barcode Scanners from the Keyboard in WinForms
Check out this thread. There's everything you need there.
If you'll be using this particular scanner, you can setup it to send a specific signal at the end of the input. To setup your scanner gun you need to read the documentation for your device, probably provided on the website of the manifacturer.
Another solution if you will be using the same scanner gun.
If your clients are going to use a lot of different scanners, it would be slight difficult to set everyone of them and track their input. In such case, you have to do it with counting the time between the keypresses (Windows cannot distinguish between barcode scanner and normal keyboard). But you still have to know the suffix of the input the scanner sends.
Most barcode scanners send a couple of control characters before and after the actual barcode data, usually something like ^B and ^C.
Take a look at what keys its actually sending by listening to the keypress event and watch for what control characters it sends. Then you can be sure when the barcode data begins and ends.
Motorola Driver and SDK for Scanners
Sounds to me that Motorola actually have a SDK for this kind of thing with a driver specific LS2208.
Lot of documentation:
Motorola LS2208 Documentation
Seriously, google moar!
The symbol or Motorola LS2208 is a pretty standard barcode scanner.
LS2208 on RJLTechnologies.com
However the issue with what you are doing is not the scanner it may be the way you are approaching the entire application from the foundation which relates to the barcode being used.If there are multiple layers of information that need to be gathered from a single code maybe it would be better to utilize a 2d barcode maybe a data matrix or something to that effect.
additionally parsing would be simplified and you can use the symbol/motorola adf pre existing library to program the scanner outside of the application either through programming barcodes or you can use the scan utility 123SCAN2 from Motorola Solutions. This means that your application is a bit more flexible is not tied down to a particular scanner and gives greater flexibility to use what ever hardware is needed instead of a codependence on a particular brand or scanner.
regards,
You want a solution that will be used to do some sort of actions after the barcode is scanned. You want to do something just after scanning a barcode by your barcode reader, right? Then this will help you more.
Write the keyPress event for the textbox which is used to scan the barcode. Now if you write any code there it will be executed every time you presses any key from keyboard or every time when barcode scanner reads a character. If you want to execute some code after the barcode has been scanned, you need to add on condition in that keyPress event. Barcode scanners has the return character (\n) associated with every barcode scan. So you need to add this condition in keyPress event. Below is the code for your reference.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (e.KeyChar == (char)Keys.Return)
{
MessageBox.Show( textBox1.Text + " scanned...");
//write your code here
}
}
}

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How to read data from Bar Code Scanner in .net windows application?
Can some one give the sequence of steps to be followed? I am very new to that.
Look at the scanner jack.
If it looks like this:
, then it's a keyboard wedge scanner. It acts like a keyboard: just types your barcode into an edit field.
If it looks like this:
, it's a serial port scanner.
You need to create an instance of System.IO.Ports.SerialPort and use it to communicate with the scanner.
If it looks like this:
(source: datapro.net)
, it's a USB scanner. From programmer's point of view, it can be either a keyboard wedge or a serial port scanner. You need to look at the manual, find out which is it and use one of the approaches above.
P.S. It will be easier if you post your scanner's model here, really.
I now use the Wasp USB WCS3905 barcode scanners attached to several of my winform (and 1 console) applications although have not noticed differences with other brands of USB scanner.
The way I always test when a new one comes along is to fire up notepad and scan a load of codes off everything that comes to hand; books, DVD, asset tags, but most importantly the stock I need to track. This will allow you visualise how the data is captured.
In my experience they all act like a user typing each character succesively on a keyboard followed by an "Enter" keypress.
For each character (NOTE: not complete bar-code) scanned in a textbox control then at least following events fire:
KeyDown
KeyPress
TextChanged
KeyUp
The Enter keystroke at the end of a scan can be used to push a form's AcceptButton
It should probably be noted that I've only used these on UK-English & US-English configured windows systems.
G-
Most modern bar code scanners act just like keyboards.
I've previously written code in C# for scanning tickets - no special tricks necessary, just make sure the input focus is in a suitable text box and scan the code!
If you're using a keyboard wedge, normally the device or wedge software allow one to prefix and/or suffix the keyboard stream with additional characters.
One can use key preview per form to "listen" for the prefix & suffix characters - and when intercepting something that resembles a barcode, the barcode text can be sent to the correct edit box or used to pop up a dialog box.
If you're setting up your own coding systems, depending on the barcode type, you can also embed special characters in to your barcode to identify what's being scanned e.g. a scan starting with SB^ would represent the scan of a stock bin.
When using the keyboard wedge, one is generally unable to determine which type of barcode one is scanning - sometimes the format can be handy to determine the content.

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