Access value outside form using thymeleaf - spring-mvc

I need to obtain vaulue of an input using thymeleaf and spring but haven't been able to do so. Since I need that value in a lot of the methods in the controller I can't put that input inside of one of the forms.
I tried to use javascript to pass on the value to a hidden input in the forms, however since I'm using th:each I'm only getting the value of the first input.
I also tried adding a string to the model and then trying to access that string with #ModelAttribute, but it didn't workout either.
This is the html:
<tr th:each="pro:${productos}">
<td th:text="${pro.id}">id</td>
<!-- More code here omitted for brevity-->
<td>
<div>
<form th:action="#{|/actualizarMas/${pro.id}|}" method="post">
<button type="submit" id="mas">+</button>
</form>
<form th:action="#{|/actualizarMenos/${pro.id}|}" method="post">
<button type="submit" id="menos">-</button>
</form>
<input name="masomenos"/>
<form th:action="#{|/${pro.id}|}" method="post">
<button type="submit">Borrar</button>
</form>
</div>
</td>
</tr>
This is the controller:
#RequestMapping(value = "/actualizarMenos/{productosId}", method = RequestMethod.POST)
public String eliminarUno(#PathVariable int productosId, RedirectAttributes redirectAttributes, #RequestParam("masomenos") String masomenos) {
//Code here using that string omitted for brevity
return "redirect:/";
}
I need to access the input with the name "masomenos", if that is posible, how could I do it?, if not, what options do I have? besides creating inputs inside all the forms.
Thank you very much.

Related

Cannot upload an image

I'm trying to update an image to my database, I defined as property model (bounded by database) the following:
public byte[] AvatarImage { get; set; }
then I created another property which store the value in the ViewModel:
public IFormFile AvatarImage { get; set; }
this steps are also described here in the doc.
Iside my form, I added the following html:
<div class="form-group text-center col-lg-12">
<img src="#Model.AvatarImage" class="avatar img-circle" alt="avatar" />
<h6>#Localizer["UploadNewAvatar"] ...</h6>
<input type="file" class="form-control" id="avatarUrl" asp-for="#Model.AvatarImages" />
</div>
when I submit the form the property AvatarImage is even null. But I don't understand why happen this, because all the other form properties are valorized correctly
Sounds like you are missing the form enctype.
Make sure you have:
<form enctype="multipart/form-data">
... inputs
<form>
Your <input type="file"> element assignment below seems to be wrong, because it uses #Model directive which outputs value of AvatarImages property (and the property is not exist in viewmodel class):
<input type="file" class="form-control" id="avatarUrl" asp-for="#Model.AvatarImages" />
The correct way is just using the property name like example below, because asp-for="PropertyName" is equivalent to model => model.PropertyName in HTML helper (assumed you have #model directive set to a viewmodel class):
<input type="file" class="form-control" asp-for="AvatarImage" />
Also don't forget to specify enctype="multipart/form-data" attribute in <form> tag helper:
<form asp-controller="ControllerName" asp-action="ActionName" method="post" enctype="multipart/form-data">
<!-- form contents here -->
</form>
Reference: Tag Helpers in forms in ASP.NET Core
First add enctype="multipart/form-data" to form ;
Then,check your #model, two situations :
1.Use Model directly, since the image is a byte array type, you need to convert the file type to byte[] during the submission process.
2.Or you could use ViewModel, and change the parameter type to viewmodel in the method.

How to post table rows data to a controller w/o using ajax in asp.net core

What is want to achieve is I have a form to adds rows with data to a html table, it's like a temporary table and all the data from it will be added in just one submit button. How can I possibly do this?
This is my sample table structure, data from it must be added to db
<form asp-action="Create">
<div asp-validation-summary="ModelOnly" class="text-danger"></div>
<div class="form-group">
<table class="table">
<thead>
<tr>
<!--some other fields-->
<th>Amount</th>
<th>Check #</th>
<th>Check Date</th>
</tr>
</thead>
<tbody>
<tr>
<!--some other fields-->
<td>
<input asp-for="Amount" class="form-control" />
<span asp-validation-for="Amount" class="text-danger"></span>
</td>
<td>
<input asp-for="Check_No" class="form-control" />
<span asp-validation-for="Check_No" class="text-danger"></span>
</td>
<td>
<input asp-for="Check_Date" class="form-control" />
<span asp-validation-for="Check_Date" class="text-danger"></span>
</td>
</tr>
<!--row 2-->
<!--row 3-->
<!--row 4-->
<!--etc..-->
</tbody>
</table>
</div>
<div class="form-group">
<input type="submit" value="Create" class="btn btn-default" />
</div>
And here is my controller code so far, i don't know what do I need to change
// POST: Books/Create
// To protect from overposting attacks, please enable the specific properties you want to bind to, for
// more details see http://go.microsoft.com/fwlink/?LinkId=317598.
[HttpPost]
[ValidateAntiForgeryToken]
public async Task<IActionResult> Create([Bind("Id,Year,Month,Document_Code,GLA_Code,Expense_Code,Function_Code,Document_Reference_No,Document_Date,Quantity,Amount,Check_No,Check_Date,Remarks,Encoder")] Book book)
{
if (ModelState.IsValid)
{
_context.Add(book);
await _context.SaveChangesAsync();
return RedirectToAction(nameof(Index));
}
return View(book);
}
What must needed to be change in my view and controller, and help will is appreciated.
Thank you.
There's a couple of issues here.
First, if you've got a table of "books" (plural), the input names need to be indexed. You then also need to accept something like List<Book> instead of Book as the param to your action method. It's a little hard to tell with just the code provided, but I'd imagine you're repeating these inputs, all with the same names for each row. If that's the case, only the values for the last item will be posted. Making it a list of items enables you to post them all.
Simplistically, that means your inputs need to have names like [0].Amount, which Razor will generate for you if you use a for loop and render the inputs like:
<input asp-for="#Model[i].Amount" class="form-control" />
If you're adding the additional rows (and contained inputs) via JavaScript, you'll need to ensure that you're generating these indexed names properly yourself. A JS templating library may help in this regard.
Second, do not use Bind. Just don't. It's awful, horrible, and kills both puppies and kittens. For more explanation see my post, Bind is Evil. Use a view model instead. As a general rule you should never post an entity class. Your entity classes serve the database and its concerns, which are almost always different from the concerns of the view. Additionally, you should never just blindly save something posted by a user. Even if you insist on using your entity class to bind to, you can improve the security and safety of your code exponentially by literally mapping the values from the posted version of the class over to a new instance you create. Then, you know exactly what is being persisted to the database (without the godforsaken Bind) and you also have the opportunity to sanitize input as necessary.
I was facing a similar problem, but using ASP.NET Core 3.1 and Razor Pages. I was looking for a way to add and remove rows from a table with JavaScript, and then post it. My problem was to post the table without Ajax. Based in the question and in the accepted answer, I could do that.
Here is Index.cshtml.cs:
public class IndexViewModel {
public string Name { get; set; }
public IList<ResourceViewModel> Resources { get; set; }
}
public class ResourceViewModel {
public string Key { get; set; }
public string Value { get; set; }
}
public class IndexModel: PageModel {
[BindProperty]
public IndexViewModel ViewModel {get; set; }
public void OnGet() {
// You can fill your ViewModel property here.
}
public void OnPost() {
// You can read your posted ViewModel property here.
}
}
Here is Index.cshtml:
#page
#model IndexModel
#{
ViewData["Title"] = "Index";
}
<form method="post">
<div class="form-group">
<label asp-for="ViewModel.Name"></label>
<input asp-for="ViewModel.Name" class="form-control" />
</div>
<div class="form-group">
<table class="table">
<thead>
<th>Key</th>
<th>Value</th>
</thead>
<tbody>
#for(int i = 0; i < Model.ViewModel.Resources.Count; i++) {
<tr>
<td>
<input asp-for="ViewModel.Resources[i].Key" type="hidden" />
#Model.ViewModel.Resources[i].Key
</td>
<td>
<input asp-for="ViewModel.Resources[i].Value" type="hidden" />
#Model.ViewModel.Resources[i].Value
</td>
</tr>
}
</tbody>
</table>
</div>
<button type="submit" class="btn btn-primary">Send</button>
</form>
Notice I've used type="hidden" because I didn't want the user to edit the table directly.
I hope you find this useful!

Spring initBinder StringTrimmerEditor - exclude some fields

In my current application by using init binder-StringTrimmerEditor we are nullifying all the values which are empty from the view/templates. But now I want to remove one field(movielist) from being nullified as this particular field when I edit the form i.e., remove all the values in the movie-list and click save button controller is getting null value instated of empty string. I want it to be as empty String instead of null value.
How do I exclude the movielist from being nullified.
<form action="#" th:object="${CustomerForm}" th:action="#{customer/save}" method="post">
<input type="hidden" th:field="*{id}"/>
<textarea th:field="*{movieList}"></textarea>
<div class="modal-footer">
<input class="btn-submit" type="submit" value="Save"/>
</div>
</form>
#InitBinder
public void initBinder(WebDataBinder binder) {
binder.registerCustomEditor(String.class, new StringTrimmerEditor(emptyAsnull:true));
}
You can look at this question
. You might have to set the allowed fields value for your databinder which will also solve a potential security concern.

Pass loop variable from Freemarker template to Spring controller

I am listing objects in a table in my view. I want to be able to edit an object using a button in the table.
<#list products as product>
<tr>
<td>${product.productName}</td>
<td>${product.price}</td>
<td>${product.quantity}</td>
<td>
<form name="product" method="post" action="/product/edit">
<input type="submit" name="submit" value="Edit this product"/>
</form>
</td>
</tr>
</#list>
The object then should be passed to a controller method:
#RequestMapping(value="/edit", method = RequestMethod.POST)
public ModelAndView edit(#ModelAttribute("product") Product product){
ModelAndView mav = new ModelAndView("product/edit");
mav.addObject("product", product);
return mav;
}
However, the product obtained by the edit method is null. How do I fix this? I tried to bind the product inside form using the code below, but that did not work either.
<form name="product" method="post" action="/product/edit">
<#spring.bind "product" />
<input type="hidden" name="${spring.status.expression}" value="${spring.status.value}"/>
<input type="submit" name="submit" value="Edit this product"/>
</form>
I want to use the POST method.
I would like to suggest a different approach. If I'm not mistaken you just want to pick an object for later editing - you don't really edit it in that very view.
If so, all you have to do is to pass an identifier of your object to your controller, but not the selected object itself.
If not, you should give us the hole story and provide the rest of the view as well.
Assuming I'm right the next question is why you need to use a form submission at all. Passing an id is best done by links - either as parameter or, if you follow REST-style, as part of the URI itself:
<!-- Link parameter -->
<#list products as product>
<tr>
<td>${product.productName}</td>
<td>${product.price}</td>
<td>${product.quantity}</td>
<td>
Edit ${product.productName}
</td>
</tr>
</#list>
<!-- REST-style -->
...
Edit ${product.productName}
...
productName isn't a good id of course. If products is a list (meaning, java.util.List) the index of the list is handy. Even in a HashMap or Set I'd create a unique id instead of using the product name.
Now that you can identify your object, select it in the backing code for later editing, but not in the view.
You'll find loads of examples of how to get link parameters in a controller. So, no need to go into detail here.
If however you insist on using a form and a POST-method then do it like this:
<form method="post" action="/product/edit">
<#list products as product>
<tr>
<td>${product.productName}</td>
<td>${product.price}</td>
<td>${product.quantity}</td>
<td>
<button value="${product.productName}" name="product" type="submit">Edit ${product.productName}</button>
</td>
</tr>
</#list>
</form>
Note that this won't work for older IE browsers (below Ver. 10), because they don't return the value, but everything that is inside the button tag.
Hidden inputs and a single submit button won't help at all, because all inputs are submitted and using different forms is not the way either.

Spring 3 checkbox list objects have null properties

I may be hopelessly lost here, but having come from a MVC.NET world I cannot for the life of me figure this one out. I'm not getting any error messages, but all object properties submitted on a form submission are null. The objects themselves are not null, just their properties.
All I want to do is have a series of objects, represented by checkboxes on the form, after the forms submits. It's a little tricky as you can can see because of a nested list arrangement. The view renders perfectly on the GET request, but seems to forget everything when posted to the server. Does anyone have any examples of such a set-up? Could anyone suggest why all my objects loose their bindings?
My Controller:
#RequestMapping(value="/Search", method = RequestMethod.GET)
public String search(Model model)
{
Period periods = new Period();
SearchModel search = new SearchModel();
search.periods = periods.BuildPeriodList();
model.addAttribute("periods", periods.BuildPeriodList());
model.addAttribute(search);
return "search";
}
#RequestMapping(value = "/Search", method = RequestMethod.POST)
public String search(#ModelAttribute("searchModel") SearchModel search, BindingResult result)
{
System.out.println(Arrays.deepToString(search.periods));
return "search";
}
My View:
<div id="searchPage">
<div id="searchForm">
<form:form action="Search" method="post" modelAttribute="searchModel">
<h2>Search</h2>
<h2>Periods</h2>
<c:forEach items="${periods}" var="period" varStatus="index">
<form:checkbox path="periods[${index.count - 1}]" id="${period.name}" name="${period.name}" value="${period.name}"/>
<label for="${period.name}">${period.displayName}</label>
<div class="subPeriods">
<c:forEach items="${period.subPeriods}" var="subPeriod" varStatus="subIndex">
<form:checkbox path="periods[${subIndex.count - 1}].subPeriods" id="${subPeriod.name}" name="${subPeriod.name}" value="${period.name}"/>
<label for="${subPeriod.name}">${subPeriod.displayName}</label>
</c:forEach>
</div>
</c:forEach>
<div class="clear"></div>
<h2>Extras</h2>
<form:checkbox path="hasImage" name="hasImage" id="hasImage"></form:checkbox>
<label for="hasImage">Image</label>
<form:checkbox path="hasPaper" name="hasPapaer" id="hasPapaer"></form:checkbox>
<label for="hasPaper">Paper Data</label>
<form:checkbox path="hasExtended" name="hasExtended" id="hasExtended"></form:checkbox>
<label for="hasExtended">Extended Info</label>
<input type="submit" name="search" value="Search"></input>
</form:form>
</div>
<div id="searchResults">
</div>
<div class="clear"></div>
It's due to some of your checkboxes being bound to your "periods" model, while others being bound to your SearchModel model. The path attribute of the form:checkbox element tells how to bind the information.
Either include this within your SearchModel, or have another #ModelAttribute("periods") in your POST method.
I'd recommend sticking to one model, plus I'm not sure if you can have more than one #ModelAttribute in a controller method, something to try, though.

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