I have a form which is used for automatic journal postings.
On that form I have a Ok command button and in closeOk method of the form I call the method from my datasource table.
In the JournalCheckPost class's infoResult() method I want to determine if the method is called from my form. I know that it can be done with caller methods but I don't know how exactly it should be done technically.
It is bad practice to make a method depend on where it is called from.
What you can do is to pass an extra parameter to the LedgerJournalCheckPost and infoResult can then check that. This can be done by introducing a boolean flag and a parm method.
I think, there can be many situations:
You want to pass some parameters from form
You want to manipulate the form (for example refresh datasource after action is complete)
Something other
But in all the cases depending on particular form is not a very good idea.
In first case you can set parameters from code using parm methods, or, better pass parameters using the Args class
In the second you can cast Args.caller to some interface that contain all the methods you want and manipulate the form using that methods (see \Classes\SysFormRun_doRe usages for example)
Related
Is there any way to override method in dynamic form?
I've created a form from code (create Form, adding DataSource, etc. and then FormRun). The problem is with the datasource validation. In normal form (in the AOT) I'd use return true in validateWrite to prevent normal validation on table.
How I can achieve this only from code? (or more precisely: when I've only class to play with)
I think the FormBuild.addMethod is what you are looking for. Provide the FormBuildDatasource object as the third argument to the addMethod method.
I have my form in my action:
$this->form = new SomeForm($this->data);
the form has a bunch of fields I don't need for one action but has stuff I need for another action. What is the best way to handle this? Create an individual form for each necessity or dynamically remove fields when I instantiate it as above?
Thanks
It sounds like you are doing a multi-part form.
I assume that you want to validate all the values submitted in your form, but just not save them.
Its sounds like you are doing an abstract form, so don't extend a base object form, rather extend BaseForm.
Don't unset the values, use the form to validate them, even if they're going to be used later.
They are saved to the form object, so you can use that to pass values to your next action, so this is helpful, plus they are validated.
Override doSave() in the form to save the objects of the form you want to save.
In my opinion for this case, extending the form to each need and applying, through the override of the setup, selectively the unset instruction, you get a code a little more readable and maintainable.
I'm invoking the ObjectDataSource InsertMethod programmatically. I've tried so save a couple of text boxes' value to the DB using the InsertParameters.Add() method, and it worked perfectly.
SqlDataSource1.InsertParameters.Add("CoName", CompanyNameBox.Text);
SqlDataSource1.InsertParameters.Add("Phone", PhoneBox.Text);
SqlDataSource1.Insert();
Now, given that I have an important number of variables, I've regrouped those variables in one object.
Now, it looks like there's no overload method that allow me to add a parameter accepting an object to the collection.
What the best way to do that? Any other alternative?
Thanks for helping.
All your paramaters will have to be provided one by one in your code, that is to say one call to add a parameter per property of your custom object.
There seem to be multiple means of passing model data from controllers in asp.net mvc to views. Its not clear to me if there's a recommended approach in the mvc v1 and v2 releases or if like most things in life, it depends. I've seen several approaches:
Option 1 - Populate the controller's ViewData dixtionary in either an icky string-based indexing way with casting in the view, or the in a strongly typed way by creating a strongly typed custom model class and passing that via ViewData.
Option 2 - Use ViewData.Model, which I'm not sure I even understand.
Option 3 - Use ViewPage.Model, in which case I'm not sure how you pass the model data from the controller.
I've seen a number of posts poo-pooing options 1 and 2 but I don't understand why. These posts seem to highly recommend 3 in most cases.
How do you approach this? Is there a standard way?
Every view 'should' have a specific model. This is sometimes more work so people use short cuts like ViewData, which works but is just not as clean and type safe in my opinion, so I prefer to have everything in the view's model.
You can then make all your views stongly typed. This is a very clean way to do so. Then in your controller you just call the view like:
YourViewModel model = new YourViewModel()
{
// initialize the data here
};
View(model);
Then in your views you can access all the data via ViewPage Model and it is all type safe and enforced from the controller as well.
EDIT from comments:
You don't need to use ViewData at all if you don't want. You can encapsulate all the data your view needs in a model. Just like the example you quoted with ProductsListViewData. It's just a model that contains all the items that were going to be stored in the ViewData. Both ways work but when you encapsulate it in a class (preferred method where everything is in the model) then all the bits and pieces are strongly typed.
ViewData is a generic container so even though you can just put anything you want into it, it is not type safe and therefore not as 'clean'. It comes down to preference and maintainability. There is only option 1 and 3. Your option 2 is misunderstood and is just option 3 in reality. There is no ViewData.Model just ViewPage.Model.
One approach you may wish to consider as your views become more complex, is to reserve the use of Models for input fields, and use ViewData to support anything else the View needs to render.
There are at least a couple of arguments to support this:
You have a master-page that requires some data to be present (e.g. something like the StackOverflow user information in the header). Applying a site-wide ActionFilter makes it easy to populate this information in ViewData after every action. To put it in model would require that every other Model in the site then inherit from a base Model (this may not seem bad initially, but it can become complicated quickly).
When you are validating a posted form, if there are validation errors you are probably going to want to rebind the model (with the invalid fields) back to the view and display validation messages. This is fine, as data in input fields is posted back and will be bound to the model, but what about any other data your view requires to be re-populated? (e.g. drop-down list values, information messages, etc) These will not be posted back, and it can become messy re-populating these onto the model "around" the posted-back input values. It is often simpler to have a method which populates the ViewData with the..view data.
In my experience I have found this approach works well.
And, in MVC3, the dynamic ViewModels means no more string-indexing!
This might be of some help:
When is it right to use ViewData instead of ViewModels?
(I know the following answer is highly arguable, but it's just the way I like to do it)
I would say use ViewData for simple data-tasks, and use the Model for the main purpose of the View. Check out Rob Conerys ViewData helper-classes here to give them a bit more Strongly typed feel:
http://blog.wekeroad.com/2010/01/20/my-favorite-helpers-for-aspnet-mvc
Using Models for absolubtely everything will bloat your project with hundreds of models just to achieve the smallest thing. I mean if you have a User-setting page, you would normally pass a User-model into the view, but if you decide to show some related data like Customers related to this User. You're stuck with the following solutions
You might have to add a List property to the User-model in order to expose the customers to the view. This leads to the Customer-property always being applied to the User-model everywhere else in the project - or make a new simpler User-model.
Make a new action that returns a partial of customers, which you can use with Html.RenderAction.
OR
you could do ViewData["Customers"] = myRepo.GetCustomersRelatedTo(user); // or something like that.
and (if using Robs helpers) in your view:
<%= Html.RenderPartial("CustomerList", Html.ViewData("Customers")) %>
add a PartialView called CustomerList that takes IEnumerable
In my humble opinion this is a cleaner solution and sure - you end up with a magic string here and there, but I'll stick to this approach until someone shows me a project with not a single magic string.
Use the tools we have in the Framework to get the job done. and Keep it simple s... ;)
Does anybody know the logic behind making DataSourceSelectArguments sealed?
I've implemented a custom DataSource (and related classes) for some custom business objects and custom WebControls. When thinking in filters (like in a grid) I discovered that the DataSourceSelectArguments is sealed. Surely, I'm missing something. (Maybe the logic is related to the fact that is nonsense to ask the DB again, just for filtering?, just a guess.)
Sorry for the delay, I was on holydays. :)
The problem is that a DataBoundControl such as ListView has a SortExpression property, but not a FilterExpression. It is fine to implement a sortable grid/list with a ListView by means of a IButtonControl WebControl that fires a PostBack and a Command event. Then you use the SortExpression or the Sort method and pass a sort expression that will fill the DataSourceSelectArguments.SortExpression and pass it to the DataSource which can construct the apropiate SQL statement (in my case) to retrieve the Data from the DB. This allows for separation between the Data and the WebControl that displays it, IMHO.
Following this pattern I was about to implement a filter by filling an extra parameter object in my DataSourceSelectArguments with the requested filter and I will have called Sort, which would have passed this arguments object to the DataSource, where I would have constructed the appropiate select clause.
I've finally solve it by "coding" the filter information in the SortExpression, but I find it ugly (for the name, in the first place: sort != filter), and I was wondering if there's a more appropiate way of doing this or if I'm missing something that is more subtle.
Edit:
Maybe a better approach would be to override ListView's PerformSelect method and ask my own implementation of the DataSourceView if it can filter, then call a special ExecuteSelect method that accepts a special DataSourceSelectArguments with a filter object. Taking care not to do anything that will break when someone use the custom ListView with a non-enhanced DataSourceView, of course.
My guess is because the class is a dumb data transfer object merely used to pass arguments to a method.
This class itself doesn't have any operations defined on it, thus what sort of polymorphism would you expect? For example, the existing methods will only know about the properties of this class, which are all settable, so there's no need to override the properties. If you added new properties, they would get ignored.
For your own method, can you create your own Arguments class that just happens to have all the same properties?