I am using Entity Framework (v4) entities. I have an entity called Car with a Year property of type integer. The Year property does not allow NULL. I have the following in my Create view:
<%= Html.TextBoxFor(model => model.Year) %>
I am required to return a new Car object (due to other requirements) in my HttpGet Create action in the CarController.
Currently, a zero is displayed in the Year textbox because the Year property does not allow NULL. I would like to display an empty textbox in the Create view. How do I do this?
Use Html Attributes Overload. In razor it would be:
#Html.TextBoxFor(model => model.Year, new { Value = "" })
Try this instead:
Html.TextBox("Year", "")
If you are using the strongly typed TextAreaFor helper, then there is no direct way to set a default value. The point of the strongly typed helper is that it binds the text area to a model property and gets the value from there. If you want a default value, then putting in the model would achieve that. You can also just switch to the non-strongly typed TextArea helper. It gives you more a bit more flexibility for cases like this:
#{
var defaultValue= "";
}
#Html.TextArea("Model.Description", defaultValue, new { Value = "added text", #class = "form-control", #placeholder = "Write a description", #rows = 5 })
Try this is you are trying to append to your field or want to modify an existing field with an empty TextBoxFor.
Html.TextBoxFor(model => model.Year, Model.Year="")
Related
I am using mvc 4, i have a form in a view (not binded to a model), its using standard html elements.
I want to populate a dropdownlist from a list value (i.e return from controller action)
also based on the selection of a value from the first dropdownlist i want to populate a second dropdownlist
can someone please guide
for the first dropdownlist you loop thru all the available options and add in <option> tags inside <select> for the second dropdownlist you need to either make bunch drop downs and hide/show them, or you create one big list and remove invalid entries base on the first list's selection. You would definitely need to do javascript for 2nd list.
If you don't want to use a Model (you should though), you will have to add the items to ViewData
I'll stub something out for you and you can complete the rest.
Inside your controller, create a list object of what you need. If you are using EntityFrameWork this will look familiar.
var list = context.Table.ToList();
List<System.Web.Mvc.SelectListItem> ddlItems = new List<System.Web.Mvc.SelectListItem>();
foreach (var item in list)
{
ddlItems.Add(new SelectListItem(){ Text = item.Text, Value = item.Value.ToString()});
}
ViewData["DDLItems"] = ddlItems;
#Html.DropDownListFor(x => x.LeagueId,
new SelectList((System.Collections.IEnumerable)ViewData["DDLItems"], "Value", "Text")
, "--Select League--", new { id = "league" })
You can define your second dropdownlist with just a placeholder until the cascade effect happens.
#Html.DropDownListFor(x => x.DivisionId, Enumerable.Empty<SelectListItem>(),
"--Select Division--", new { id = "ddlDivision" })
Your going to need to use JQuery and fire and event when the dropdown changes, and then use Ajax to make a call back to the controller. Theres 2348239 examples online about making Ajax calls, know how to do that because it's done all the time in MVC.
I'll let you figure that part out. One hint, inside the Ajax call you can pass data to the controller. something like this data: { leagueId: value } where value is the value of the dropdownlist you want to cascade off of. leagueId must match type and name of the parameter your controller will expect.
Return a Json object from your controller like so...
public JsonResult GetDivisions(int leagueId)
{
var division = //similar to before, fill a list.
return Json(divisions, JsonRequestBehavior.AllowGet);
}
And then in the success function of your Ajax call, you will populate the Second dropdownlist.
success: function (data) {
$.each(data, function (index, item)
$('#ddlDivision')
.append($('<option></option>')
.val(item.Value)
.html(item.Text))
item.Value and item.Text can be anything, just as long as the Json you return as the properties of Text and Value
IE...
var divisions = (from x in context.Division
select new
{
Text = league + " " + x.Region,
Value = x.DivisionId
}).ToList();
I have a "Thing" domain class, where each Thing has an record number (which is not the automatically generated id), that the user will use to access a Thing:
class Thing {
...
String recordNumber
...
}
There is a form to look for a Thing, knowing its recordNumber:
<g:form action="search">
<input name="recordNumber">
<g:submitButton name="btn" value="go to this Thing"/>
</g:form>
I would like to use a validation process in this form: if the recordNumber is not found (Thing.findByRecordNumber(recordNumber) == null), then the input field must turn in red, and a tooltip must show the error message "record number not found".
As far as I know/read (I'm a grails rookie), this has to be written as a constraint in the Thing class:
static constraints = {
recordNumber validator: { n -> Thing.findByRecordNumber(recordNumber) }
}
The problem is: I do not have in this form all the "Thing" properties to populate, just the recordNumber one, so I just can't call
new Thing(params).validate()
How to call validation on just one field, not on the whole object ?
If this is your main question, although I see others there:
"How to call validation on just one field, not on the whole object ?"
You can pass a list of values to validate and it will only validate those properties
new Thing(params).validate(["recordNumber"])
http://grails.org/doc/latest/ref/Domain%20Classes/validate.html
Validation is for constraints for domain class properties. You need an action in your controller:
def search = {
if(params.recordNumber && Thing.findByRecordNumber(params.recordNumber)){
redirect(action: "show", params:[id:Thing.findByRecordNumber(params.recordNumber).id])
}else{
flush.message = "No record found"
render(view:'VIEW_WITH_SEARCH_FORM')
}
}
If you want to validate without refreshing page, write a javascript code.
<% string disabled="new {disabled='disabled'}"; %>
<%= Html.DropDownList("clientId", someObject, disabled)%>
In the above code I want the text disabled to be replaced by what ever value I set that string to. When I check the HTML source on the page, I see that new {disabled='disabled'} has been added as a new item in the dropdown list instead of a property. How do I fix this?
The third parameter of DropDownList helper must be an object that contains the HTML attributes or object of type IDictionary<string, object>.
This is the proper solution:
<% var disabled = new { disabled = "disabled" }; %>
I have a scala form with several fields.The fields in the form map to the member variables of a Java class. I want to bind one of the fields(say userId) with a value (I dont want the user to enter values for this field. Instead i want to pass this as a parameter to the scala template). However, i was unable to manually bind a form field. Any help is highly appreciated.
See the sample below for easier understanding :
`#(itemForm: Form[Item], user: User)
#import helper._
#main("Item list") {
#if(user != null) {
#form(routes.Application.newItem()) {
#itemForm("userId") = #user.id /**I want to bind the userId form field */
#inputText(itemForm("title"))
#inputText(itemForm("description"))
#inputText(itemForm("price"))
<input type="submit" value="Create">
}
}
}`
In this case it would be better to pass it as action's argument (remember to modify routes declaration)
#form(routes.Application.newItem(user.id)){
....
you can also just use common html
<input type="hidden" name="userId" value="#user.id" />
edit:
Validation in action.Note: it doesn't make sense to display errors on the page next to hidden field, so you do not need placeholders for error messages. It's up to you to pass VALID value into the hidden field. Displaying validation errors to user who can not change the value of hidden field is bad conception.
public static Result newItem(){
Form<ItemModel> itemForm = form(ItemModel.class).bindFromRequest();
if (itemForm.hasErrors(){
return badRequest(newItemView.render(itemForm));
}
itemForm.get().save();
return ok("Your new item is saved...");
}
I have a form, created with Zend_Form, with method = GET used for searching records with elements as below:
[form]
user name [input type="text" name="uname"]
[input type="submit" value="Search" name="search"]
[/form]
After form is submitted all the GET parameters along with submit button value are appearing in the url.
http://mysite.com/users/search?uname=abc&search=Search
How to avoid submit button value appearing in the url? is custom routing the solution ?
When you create your element, you can simply remove the name attribute that was automatically set at creation
$submit = new Zend_Form_Element_Submit('search')->setAttrib('name', '');
Or inside a Zend_Form
// Input element
$submit = $this->createElement('submit', 'search')->setAttrib('name', '');
// Or Button element
$submit = $this->createElement('button', 'search')->setAttribs(array
(
'name' => '', 'type' => 'submit',
);
When a form gets submitted, all of its elements with their names and values become a part of a GET / POST - query.
So, if you don't want an element to appear in your GET - query, all you need to do is to create this element without a name. That's probably not the best approach, but since we're talking about the 'submit' element, I guess it doesn't matter that much.
Looking at Zend_View_Helper_FormSubmit helper, you can see that it's creating the 'submit' element and setting its name. So, the possible solution would be to create your own view helper and use it for rendering the 'submit' element instead of the default helper.
You can set a custom helper with
$element->setAttribs( array('helper' => 'My_Helper_FormSubmit') );
Then build your own form element class and remove the name attribute from the element with preg_replace. The beauty of it is, it will not interfere with the other decorators.
So the something like this:
class My_Button extends Zend_Form_Element_Submit
{
public function render()
{
return preg_replace('/(<input.*?)( name="[^"]*")([^>]*>)/', "$1$3", parent::render(), 1);
}
}
You can remove name attribute for submit button in javascript.
jQuery example:
$('input[name="submit"]').removeAttr('name');
In the controller that represents the form's action, redirect to another (or the same controller) only including the relevant params.
Pseudocode:
$params = $this->getRequest()->getParams();
if isset($params['search'])
unset($params['search']);
return $this->_helper->Redirector->setGotoSimple('thisAction', null, null, $params);
handle form here
This is basically the same idea as Post/Redirect/Get except that you want to modify the request (by unsetting a parameter) in between the different stages, instead of doing something persistent (the images on that Wiki-page shows inserting data into a database).
If I were you, I would leave it in. IMO it's not worth an extra request to the webserver.