Programmatically updating with detailview




















You could pass that IDictionary you need, instead of the different EventArgs. Friday, June 12, PM. User posted those are the controls, you need to use findcontrol method to find those then u need to utilize those.

Thursday, June 11, PM. User posted I tried that and it works, depending on where I call the code from. FileName lblMessage. Text Catch ex As Exception lblMessage.

User posted In the ItemUpdating event, the data to send to the DataSoruce has already been collected. Changing the content of the controls will not influence that anymore. Instead, you will have to change the NewValues that are passed in e.

Friday, June 12, AM. User posted That's the approach I originally was taking see the first post in this thread but was getting the "Object reference not set to an instance of an object" error.

User posted It is the right event. However, there is a catch. The values-collections only hold the fields that are to be updated.

If fupChart is a readonly field, it won't be in e. Not sure it will be in e. OldValues either. If fupChart is a key field, it will be in the keys collection. It's probably best to set a breakpoint in the ItemUpdating and use the debugger to browse e. See if you can find the fields value anywhere. User posted I just figured it out. FileName This works. User posted Works like a charm.

Thanks for you help! Take our short survey. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked 11 years, 1 month ago. Active 4 years, 9 months ago. Viewed 2k times. Now I want to Provide Update feature programmtically. How can I do this?.. Improve this question. Do you want to let the user update details information? Add a comment. Active Oldest Votes. Set the dropdown to autopostback.

You'll get the desired behavior without a full postback. You might be able to do better, but this will work. Improve this answer. Broam Broam 4, 1 1 gold badge 22 22 silver badges 38 38 bronze badges.

Once the ObjectDataSource has been added to the page and configured, we're ready to add data Web controls to the page to both display the data and provide a means for the end user to modify it. We'll look at the GridView, DetailsView, and FormView separately, as these data Web controls differ in their data modification capabilities and configuration.

As we'll see in the remainder of this article, adding very basic editing, inserting, and deleting support through the GridView, DetailsView, and FormView controls is really as simple as checking a couple of checkboxes. There are many subtleties and edge cases in the real-world that make providing such functionality more involved than just point and click.

This tutorial, however, focuses solely on proving simplistic data modification capabilities. Future tutorials will examine concerns that will undoubtedly arise in a real-world setting. Start by dragging a GridView from the Toolbox onto the Designer.

At this point the GridView's declarative markup will be:. The GridView control provides built-in support for row-level editing and deleting.

Configuring a GridView to support deleting adds a column of Delete buttons. When the end user clicks the Delete button for a particular row, a postback ensues and the GridView performs the following steps:.

The values assigned to the DeleteParameters are the values of the DataKeyNames field s for the row whose Delete button was clicked. If it's missing, the DeleteParameters will be assigned a value of Nothing in Step 1, which in turn will not result in any deleted records in Step 2.

The DataKeys collection is stored in the GridView s control state, meaning that the DataKeys values will be remembered across postback even if the GridView s view state has been disabled. However, it is very important that view state remains enabled for GridViews that support editing or deleting the default behavior. If you set the GridView s EnableViewState property to false , the editing and deleting behavior will work fine for a single user, but if there are concurrent users deleting data, there exists the possibility that these concurrent users may accidentally delete or edit records that they didn't intend.

NET 2. To add deleting capabilities to a GridView, simply go to its smart tag and check the Enable Deleting checkbox. The CommandField renders a column in the GridView with buttons for performing one or more of the following tasks: selecting a record, editing a record, and deleting a record.

At this point, believe it or not, we're done with adding deleting support to the GridView! As Figure 11 shows, when visiting this page through a browser a column of Delete buttons is present. If you've been building this tutorial from the ground up on your own, when testing this page clicking the Delete button will raise an exception.

Continue reading to learn as to why these exceptions were raised and how to fix them. If you're following along using the download accompanying this tutorial, these problems have already been accounted for. However, I encourage you to read through the details listed below to help identify problems that may arise and suitable workarounds. DeleteProduct , however, only accepts a single input parameter, hence the exception. Since every product in the Northwind database has at least one record in Order Details , we cannot delete any products until we first delete the product's associated order details records.

For our tutorial, let's just delete all of the records from the Order Details table. In a real-world application we'd need to either:. Let's just delete all of the records from the Order Details table to circumvent the foreign key constraint. MDF node, and choose New Query. After clearing out the Order Details table clicking on the Delete button will delete the product without error.

When clicking on the Delete button a postback ensues and the record is deleted. This can be dangerous since it is easy to accidentally click on the wrong row's Delete button. In a future tutorial we'll see how to add a client-side confirmation when deleting a record. Along with deleting, the GridView control also provides built-in row-level editing support. Configuring a GridView to support editing adds a column of Edit buttons. From the end user's perspective, clicking a row's Edit button causes that row to become editable, turning the cells into textboxes containing the existing values and replacing the Edit button with Update and Cancel buttons.

After making their desired changes, the end user can click the Update button to commit the changes or the Cancel button to discard them. In either case, after clicking Update or Cancel the GridView returns to its pre-editing state. From our perspective as the page developer, when the end user clicks the Edit button for a particular row, a postback ensues and the GridView performs the following steps:. At this point the markup is returned to the browser, allowing the end user to make any changes to the row's data.

When the user clicks the Update button, a postback occurs and the GridView performs the following steps:. The primary key values assigned to the UpdateParameters in Step 1 come from the values specified in the DataKeyNames property, whereas the non-primary key values come from the text in the TextBox Web controls for the edited row.

If it's missing, the UpdateParameters primary key value will be assigned a value of Nothing in Step 1, which in turn will not result in any updated records in Step 2.

Editing functionality can be activated by simply checking the Enable Editing checkbox in the GridView's smart tag. As we saw earlier, the CommandField contains a number of ShowXButton properties that indicate what series of buttons are displayed in the CommandField. That's all there is to adding rudimentary editing support. In addition to asking users to edit foreign key values directly, the editing interface's interface is lacking in the following ways:.

These are all shortcomings that we'll have to live with for now, but will be addressed in future tutorials. As we've seen in earlier tutorials, the DetailsView control displays one record at a time and, like the GridView, allows for editing and deleting of the currently displayed record.

Both the end user's experience with editing and deleting items from a DetailsView and the workflow from the ASP. NET side is identical to that of the GridView.



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