locked
ReportViewer Dropdown Postback - How does it know? RRS feed

  • Question

  • User-331009151 posted

    Could anybody tell me what criteria a report parameter must meet in order for the ReportViewer control to decide that a dropdown can do a postback?

    I am a little stumped as I have a report that has numerous dropdown lists on it but not all of them do a postback when a selection is changed, only some? Is this related to dependencies in some way?

    Tuesday, August 2, 2016 12:00 PM

Answers

  • User-331009151 posted

    Never mind, I have worked it out. It would appear that any filter parameter that is a dependent of another filter parameter should be flagged as being able to post back. This has sorted me out in this instance.

    • Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM
    Wednesday, August 3, 2016 10:56 AM

All replies

  • User-2057865890 posted

    Hi Scout7,

    I am a little stumped as I have a report that has numerous dropdown lists on it but not all of them do a postback when a selection is changed, only some? Is this related to dependencies in some way?

    Dropdown has a property name AutoPostBack. Set this property to true if the server needs to capture the selection as soon as it is made. AutoPostBack property works with SelectedIndexChanged event.

    reference: DropDownList AutoPostBack

    Best Regards,

    Chris

    Wednesday, August 3, 2016 7:40 AM
  • User-331009151 posted

    Thank you for your reply but maybe I have not explained myself very well. I am writing a replacement for the reportviewer control. When designing an SSRS report that will then be viewed via the report viewer control on a page how does the report viewer control work out if a filter dropdown list should postback or not? As far as I can see when creating a report there is no flag that says a parameter should cause a postback. I am assuming that it has something to do with parameter dependencies and query based results but I would like to now what the actual rules are that lets the reportviewer control decide.

    Wednesday, August 3, 2016 8:09 AM
  • User-331009151 posted

    Never mind, I have worked it out. It would appear that any filter parameter that is a dependent of another filter parameter should be flagged as being able to post back. This has sorted me out in this instance.

    • Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM
    Wednesday, August 3, 2016 10:56 AM