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Is this possible?
Step 1: Set up a Crystal Reports engine (e.g., via a .NET backend).
Step 2: Generate reports on the server-side and export them as PDF, Excel, or other formats.
Step 3: Use APIs to deliver these reports to the React front-end.
Step 4: In your React application, display the generated report by embedding the PDF in an or offering it as a download.
If not my issue is, I have to use already created crystal reports, in a Windows Form to react (Core web API) conversion project. what is the possibility of using the existing reports?
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Answers
The Crystal portion must run on Windows under .NET Framework. Can’t use .NET Core. So highest you can go is 4.8.1.
Your main app can call the Crystal app, pass the rpt file path, parameters, logon info, export format, export file, etc. It can then deliver the exported file to the end user.
If you don’t want to develop the Crystal portion yourself, there are 3rd-party Crystal Reports automation packages that provide a command line API.
As far as I know, this is no direct support for using Crystal Reports in ASP.NET Core at this time.
If you’d like to expose existing Crystal Reports to React client users (migrate from webform to React + ASP.NET Core APIs), as you mentioned in possible approach/steps, you can try to make webform project expose Crystal Reports as webmethods or service, then consume the service form React client to render generated PDF report. And if you do not want React client communicate data with old webform app, you can implement/configure your ASP.NET Core API to serve as an intermediary proxy between the React app and the webform app.
Besides, it might be better to redesign and reconstruct projects, make ASP.NET Core API to expose data to client app, and implement report features with pure js solution based on fetched data on React client.