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powershelloverloadingzxingzxing.net

Issue with QR Decoding using Zxing.Net in Powershell - Cannot find an overload for "Decode" and the argument count: "1"

I am trying to decode an QR Code in PowerShell with using Zxing.net (https://github.com/micjahn/ZXing.Net)

There is a HowTo at this page but I am not able to use it that way: https://github.com/micjahn/ZXing.Net/wiki/Using-ZXing.Net-with-Powershell

Everytime I run the script I receive the following error message: 

Cannot find an overload for "Decode" and the argument count: "1".
At C:\Users\ww\Desktop\reader.ps1:13 char:1
+ $result = $reader.Decode($bitmap)
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodException
    + FullyQualifiedErrorId : MethodCountCouldNotFindBest

My whole script is:

Add-Type -Path "C:\Users\ww\Desktop\zxing.net\lib\net45\zxing.dll"
$reader = New-Object -TypeName ZXing.BarcodeReader
$reader.Options.TryHarder=1
# set TryHarder option to true, other options can be set the same way
$bitmap = [System.Drawing.Bitmap]::FromFile("C:\Users\ww\Desktop\abc.bmp")
$result = $reader.Decode($bitmap)
$bitmap.Dispose()
$result.Text

I only know "overload" from Java, where I can use different parameters for the same function, but in this case it makes no sense to me (I am not a very experienced programmer).

Is it possible that I am using the wrong .dll? I downloaded the Nuget-Package from https://www.nuget.org/packages/ZXing.Net/0.16.5, then extracted it via 7-Zip. I have tried various .dll (net40, netcoreapp3.0, portable, net20,...) but the result was always the same.

I also found this Github thread, where it seems rather easy to get everything working.

Could anyone give me a hint what is wrong with my implementation? Thank you!

Solution

  • The script as-is should work fine. Make sure you are using the .dll for the appropriate version of .NET installed on your system. For example, I have .NET version 4.8, so I used the .dll for the highest version available, 4.7. My file-path is C:\...\ZXing.Net.0.16.5.0\net4.7\zxing.dll .

    Add-Type -Path "C:\Windows\System32\WindowsPowerShell\v1.0\Modules\Zxing\zxing.dll"
$reader = New-Object -TypeName ZXing.BarcodeReader
$reader.Options.TryHarder = 1 # set TryHarder option to true, other options can be set the same way
$bitmap = [System.Drawing.Bitmap]::FromFile("C:\Users\testUser\Pictures\QR.png")
$result = $reader.Decode($bitmap)
$bitmap.Dispose()
$result.Text

    Console Output: https://www.youtube.com/watch?v=oHg5SJYRHA0