Hello @GuoJunjie ,
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The error message did mention => The control is successfully added … but it can’t be enabled in current design. So you may consider why it can’t be enabled. Probably you didn’t open the designer view for one of the web page that you are developing on.
Please try to select and right-click the file(for example, xx.aspx) => click "View Designer" => and then try to add your control to the toolbox(right-click any white space in Toolbox window => click "Choose Items…" => switch to "COM Components" tab => check your control => confirm if it is added successfully and listed in Toolbox window).
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Dear Albert Kallal :
Thank you very much. I’m newer for Web App developer. We have developed a package Wpf Application for industry real time control with some third wpf’s dll. Now we want to transfer part of control information to Web . The Wpf App is still be used and extend for new requirements . We wangt to refresh the Web App at same time . Is there any way to do that within Vs2019?
Thank you very much for your help again.
Well, you can certainly build some page on a web site, but that page of it own accord can't say communicate with say some hard ware device. If you have some kind of system that can push out data to say a database, then a web site can display such information. However, as I stated, those desktop controls and interface simply can't be used in a web browser. You can no more do this then you can turn a bicycle into a helicopter. (why: because a bicycle and a helicopter are not the same thing - that's why!!!). So, you don't say "what kind" of control you want to transfer to the web. That web based browser say running on my computer has ZERO ability to mess around with my hardware (let alone use windows desktop controls). So, if some type of hard is to be attached to say some computer that logs data to a database, then a web display can thus consume that data. However, the web browser is locked down from touching hardware on the computer the browser is running. (not like YOUR web site going to say look around at my hardware, or grab my banking or accounting files on my computer). So, a web browser is 100% sand boxed from touching the computer hardware, and if web browsers were not locked down this way, then no one would EVER risk using a web browser, since when you come to my site to look at a cute cat picture, the web site could then start messing around with YOUR computer and grab files and do all kinds of things.
So, we dealing with two issues here:
Software written for the windows desktop can no more run on a Apple Mac, or say a Android phone - they are vast different architectures here. So, those desktop components can't be used for or in a web browser.
And then the next issue is what kind of information are you to display in that web browser? You can quite much display any information and have some "very" cool looking dashboard in a browser. However, that information for that display has to come from the web server. So that web browser can't touch, or communicate with ANY of the hardware from the "client" computer that hosts that browser, since as I noted this would be far too great of security risk. (the web browser has ZERO knowledge of your hard drive, files, and any devices attached to that computer.
Now, if some hard ware data device "sends" data to some server? And that server shares its data with the web server? Ok, now ANY web browser can thus receive data from that web server, and thus display some cool dashboard and system.
However, the client side web browser + system can't touch or communicate with ANY hard ware on that computer that runs the browser - (its in that sand box).
So, a web based UI can quite much be anything you dream up, and can certainly be as rich and cool as a desktop program. But, that would only be the "UI" part, since the web browser as noted can't touch or communicate with hard ware attached to that same work station.
So, web based software can't use "windows" controls anymore then software written for FoxPro or vb can be used on a android phone, or some Atari computer. And web based software has the additional limitation that it can't touch nor communicate with any hardware on which that computer that is running that browser instance.