Just i want to show to the user customized message from SQL Server Database or Predefined based on my Query Response. Do we have any mechanism to show to the user on Survey 123 forms . and Any Static messages those can be configurable in xls forms ? to show to the user that , what exactly the issue is ?
I'm unsure of the scenario you are describing. Are you asking to show a message after submission, or loading from the Inbox?
There are several message options available in the XLS form, but they relate to in form processing. There currently is not a way to have a message display based on an interaction with the feature service.
After Submitting the Survey, i Want to see the messages like "Successfully Submited and Do you want to submit another survey ?" link to go back in Web version.
I want to validate the input value entered in the suvey form against the SQL Server Database and display the messages according to that validations (Warning , Error and Info messages). How to do those ?
Currently surveys published by Survey123 Connect cannot set a post-submission message.
Data validation can be done in-form by setting the validation criteria in the constraint column of an XLS form. See Formulas—Survey123 for ArcGIS | ArcGIS
I took below note from ArcGIS Site
Common uses for webhooks include sending notifications via email or SMS, posting messages to social media, automatically writing records to a spreadsheet, and updating enterprise databases.
Can We USE RESTful Service to handle POST Request to update and validate the databases ?
Yes, you could run a set of validation rules as part of a webhook; however this occurs after the data has been submitted to the feature service (database table). If you wanted to conduct the validation and migrate to another DBMS, that would be a use case for a webhook.
This is probably not the appropriate forum to debug ASP.net request handling. That being said, it sounds like your handler is not providing a response to the event. I would recommend capturing a webhook request so you have the a sample payload and from there developing with a client like Postman to test the handler.