Say I have a database record with 7 fields and I just want to edit the contents of field 1. So I hit my GET EDIT action, it renders the strongly typed view with my viewmodel and I go ahead and update field 1. However, my POST action contains 'mapping' for all fields as below. So will entity framework 'overwrite' all 6 other fields in the underlying database with the unchanged value or will it only just change field 1?
Just looking for further clarification after giving the previous related answer (c# edit method overwrite all or only save changes fields?) some more thought given that I am explicitly specifying each field in the edit method.
EDIT POST method extract -
db.entities.find(x)
entity.field1= viewmodel.field1;
entity.field2= viewmodel.field2;
entity.field3= viewmodel.field3;
entity.field4= viewmodel.field4;
entity.field5= viewmodel.field5;
entity.field6= viewmodel.field6;
entity.field7= viewmodel.field7;
db.savechanges()
FYI - this is my first proper MVC app.
Many thanks
Related
I'm creating a web app with symfony. I'm currently building the forms and as I've never used the ManyToMany relation I'm having some problem with retrieving the information.
The form I'm working with is this one:
The point is that when I'm retrieving the information of the array in the twig template, the data property inside the array shows empty, when there is Alumne's entities created. Let me show you.
Twig template (create page):
As you can see, what I pretend is to retrieve the info of every Alumne entity inside the array.
What I get doing this is:
The alumnes field is completly empty. But if I change the form Builder to this:
(I have also changed a little bit the twig template to make it more readable)
It works!
And as you can see there is an Alumne created.
The point is, as you can see, the select and option tag it creates is kinda ugly, I want to custom so it can fit the rest of the forms. So that's why I need a CollectionType in the builder and I don't know what I'm doing wrong. Also if I check the dump(form.alumnes.vars.data) it shows empty.
The issue here is, that you use the CollectionType instead of the EntityType. To load data from the Database into a form, you should use the EntityType https://symfony.com/doc/current/reference/forms/types/entity.html
If you leave the type out, Symfony will try to guess what form element to use and will (correctly) guess the EntityType
I'm working with Symfony2 to set up a form, where a Shelf-Entity can be edited.
A shelf contains a collection of Readable-Entities (e.g. Book, Magazine, etc. - all inherit from Readable).
The user has the possibility to add more Readable-Entities (the form is extended via JavaScript) and from a dropdown he can select the type of Readable he wants to add. Depending on the selected dropdown-value, different form fields are rendered. So far so good.
Now, when the form is submitted to the server, depending on the Readable-Type the user selected in the form, a different entity-type should be instantiated.
If I don't do anything, Symfony just instantiates the base class Readable (and not Book, Magazine, etc.).
How can I tell Symfony to instantiate the correct type of Readable depending on the selected value from the dropdown?
I tried with FormEvent-Listeners, but:
in PRE_SUBMIT I only get an array containing the "raw" form data with $event->getData(), i.e. no entities have been instatiated so far. However, at this stage, I still have access to value of the dropdown.
in SUBMIT the form data was already assigned to the appropriate entities. Also the new Readable was already instatiated with the base Readable-Class. But now, I cannot access anymore the value from the dropdown.
What is the correct way to do this?
EDIT
Added a minimal Code-Example for the Shelf FormType:
https://gist.github.com/anonymous/401495b701982adafb96
Code for infinite_form_polycollection:
https://gist.github.com/anonymous/b5f0ed10ca9c52177f01
Have you tried looking at this part of the doc? As "embedding a form" seems to fit your needs.
It seems that there was something wrong with the PHP-Files of the PolyCollection in the vendor-directory, because after removing everything related to the Infinite Form Bundle from the vendor-dir and reinstalling it with composer, everything is working now. But thanks for your efforts YoannCh
I have been attempting to create a form where a user can simply press a button and the form will add a new field for the user to use. I have 2 of these dynamically added field types.
Firstly a field where a user can upload files, by pressing the add button another field is pasted underneath the current field and is ready for use.
I have followed an old guide on how to get this done with a bit of ajax and jQuery.
This guide to be exact: http://www.jeremykendall.net/2009/01/19/dynamically-adding-elements-to-zend-form/
As you can see it's from 2009 and a bit outdated yet it still works under the current Zend Framework version 1.11.11
The problem however arises now that i want an edit / update version of the form. I need to populate it's fields but first of all i need to create enough fields for the data to be stored in. So when there's 3 files that have been uploaded it should create 2 additional fields and place the 3 file names in these fields ready to be edited and updated. Simply using $form->populate($stuff) is not going to work
I just have no idea how to accomplish this and the tutorial on dynamically added fields only goes as far as the addAction and not how to create the editAction under these conditions.
Is there any tutorial out there on how to create and manage forms such as these? I'm sure i am not the only one who's had the idea to builds these kind of forms?
I can add my code if there's a request for it but it's the same as the example from the guide, just a different set of elements in the form.
Adding a small example of it's use.
A user adds an item with 3 files, these files are uploaded along with a filename so in the database it appears like this : File_Id : '1' , File_Name : 'SomeFile' , File_location : 'somewhere/on/my/pc/SomeFile.txt'.
Now the user realizes he forgot a file or wants to delete a file from that list, he goes to the edit page and here i want the form to display the previously added filenames. So if there's 3 files it shows 3 and when there's 2 it shows 2 etc. How do i build a form to dynamically add fields based on the number of uploaded files and then populate them?
Any advice on how to handle this is well appreciated :)
You can make use of the semi-magic setXxx() methods of the form.
Inside the form:
public function setFiles($files) {
foreach ($files as $file) {
$this->addElement(/* add a file element */);
//do other stuff, like decorators to show the file name, etc.
}
}
In your controller:
$files = $model->getFiles();
$form = new Form_EditFiles(array('files' => $files));
By passing an array with key files you will make the form try to call the method named setFiles(), which you have conveniently provided above.
This should push you in the right direction, or so I hope at least.
If I understand you correctly you want to populate file upload fields, which is not possible because of security reasons.
Edit:
You can add Elements inside of the Controller via $form->addElement() (basicly just like the $this->addElement() statements in the Tutorial)
I have a two Symfony forms:
ShoppingListForm
ShoppingListItemForm
I'm embedding the ShoppingListItemForm inside the ShoppingListForm many times. i.e. A shopping list contains many items.
So the ShoppingListItemForm consists of two widgets:
item_id (checkbox)
shopping_list_id (hidden - foreign key)
What I would like to do is delete the corresponding ShoppingListItem object if the object exists and the checkbox is left unchecked.
I'm not sure how this delete would occur? Would I use a post validator to see which fields have/haven't been checked? I'm a bit lost on this one.
I'd do this by over-riding the ShoppingListForm's updateObject method and putting your custom delete() etc calls in there (be sure to call parent::updateObject() within it).
Depending how you implement it, you may also need to remove the embedded forms and their values to ensure saving still works correctly for the remaining objects. Try without, but if you do, you need to clear the following:
unset($taintedValues['ShoppingListItem'][$key]);
unset($this->embeddedForms['ShoppingListItem'][$key]);
unset($this->validatorSchema['ShoppingListItem'][$key]);
unset($taintedFiles['ShoppingListItem'][$key]);
If you want to see a custom updateObject method to get an idea how to interact with values etc:
http://www.symfony-project.org/forms/1_2/en/11-Doctrine-Integration#chapter_11_sub_customizing_the_updateobject_method
personnally, I would loop through the existing list items to see whether the corresponding checkboxes are checked in the action, and call the delete() method on the items for which it is not the case. I don't think it is the purpose of a post validator, I would do this directly in the action.
OK, let's start with the Html.Textbox. It is supposed to contain text read from a file. The file read is based on what the user picks from a dropdown list.
The first time it is fine. The user picks a value from the dropdown list. The controller uses that value to read some text from a file, and returns that text to the view via the view model. Everything is fine.
THen the user picks another value from the dropdown list. The controller reads a new value from a file and returns it via the view model. Debugging to the LINE BEFORE THE HTML.TEXTBOX is set in the view shows that the model contains the correct value. However, the textbox itself still shows the PREVIOUS value when the page displays!
If I switch from Html.Textbox to a plain input, type="text" html control, everything works fine. That's not so hard, but the same thing happens with my dropdown list -- I can't set the selected value in code. It always reverts to whatever was chosen last. Rendering a "select" tag with a dynamically-generated option list is a pain. I would love to be able to use Html.Dropdown.
What am I missing here?? This is such a simple thing in webforms!
When you post a form, the values that are posted are put into ModelState. When the HtmlHelper renders an html iunput element, e.g. Html.TextBoxFor(x => x.FirstName), it'll search various locations to get the value for the textbox... ModelState is before ViewData.Model in the list of locations. So there for, the previously posted value will appear in your textbox.
To fix this you could clear the ModelState value or update the ModelState value. BUT I would kinda view that as a hacky way of getting around the problem.
The real issue has more to do with the flow of the posts and requests. I would personally look into that and maybe implement the PRG (Post Redirect Get) pattern.
HTHs,
Charles
Following on from what Charles/Charlino said:
Model binding updates the ModelState object, which contains validation and model binding errors that are collected during model binding.
Inside an action method, model binding has occurred already to update the model, and generated the ModelState object. If you now update the value on the model inside the action, you must also manually update the model state (since the helpers use it to generate their HTML). Below is an example:
model.CaptchaIsValid = CaptchaService.ValidateAndExpireCaptcha(model.CaptchaAttempt);
if (!model.CaptchaIsValid)
{
ModelState.AddModelError("CaptchaAttempt", "Incorrect - please try again");
}
// I'll clear the value on each attempt, to force them to re-enter a CAPTCHA.
model.CaptchaAttempt = string.Empty;
// Since I updated the model, I must create a new ValueProvider result...
ValueProviderResult clearedValue = new ValueProviderResult(
model.CaptchaAttempt,
model.CaptchaAttempt,
CultureInfo.CurrentCulture);
// ... and update the ModelState's value.
ModelState.SetModelValue("CaptchaAttempt", clearedValue);
The biggest issue I see here is that you are trying to do a postback within MVC. That model is really not supported, and is actually way more trouble than it is worth (as it seems you are finding out). I would recommend using Ajax to update the contents of the dropdown dynamically.