I've run into a bit of a design issue, and I'm curious if anyone else has run into something similar.
I have a fairly complex model which I have an Edit action method for. Each individual entity has two images associated with it, along with other, more mundane data. These images are [Required] upon creation. When editing an entity, however, these images already exist, since, again, they were required upon creation. Thus, I don't need to mark them as required.
Adding a bit of a monkey wrench to the whole thing is my custom image validation attribute:
public class ValidateFileAttribute : ValidationAttribute
{
public override bool IsValid(object value)
{
var file = value as HttpPostedFileBase;
if (file == null)
{
return false;
}
string[] validExtensions = { "jpg", "jpeg", "gif", "png" };
string[] validMimeTypes = { "image/jpeg", "image/pjepeg", "image/gif", "image/png" };
string[] potentialFileExtensions = file.FileName.Split('.');
string lastExtension = potentialFileExtensions[(potentialFileExtensions.Length - 1)];
string mimeType = file.ContentType;
bool extensionFlag = false;
bool mimeFlag = false;
foreach (string extension in validExtensions)
{
if (extension == lastExtension)
{
extensionFlag = true;
}
}
foreach (string mt in validMimeTypes)
{
if (mt == mimeType)
{
mimeFlag = true;
}
}
if (extensionFlag && mimeFlag)
{
return true;
}
else
{
return false;
}
}
}
What I'd ideally like to do would be to create some kind of [Optional] attribute which would bypass the image validator altogether if new files aren't POSTed along with the rest of the form data.
Is something like this possible? If not, how would the collective wisdom of Stack Overflow address the problem?
you might be interested in following article...
but i have to say i do agree with most in the article.
mainly the part : conditional validation
http://andrewtwest.com/2011/01/10/conditional-validation-with-data-annotations-in-asp-net-mvc/
hope this will helps.
Related
So when writing UI in GTK it's generally preferrable to handle reading of files, etc. in an Async Method. things such as listboxes, are generally bound to a ListModel, the items in the ListBox updated in accordance with the items_changed signal.
So if I have some class, that implements ListModel, and has an add function, and some FileReader that holds a reference to said ListModel, and call add from an async function, how do i make that in essence triggering the items_changed and having GTK update accordingly?
I've tried list.items_changed.connect(message("Items changed!")); but it never triggers.
I saw this: How can one update GTK+ UI in Vala from a long operation without blocking the UI
but in this example, it's just the button label that is changed, no signal is actually triggered.
EDIT: (Codesample added at the request of #Michael Gratton
//Disclaimer: everything here is still very much a work in progress, and will, as soon as I'm confident that what I have is not total crap, be released under some GPL or other open license.
//Note: for the sake of readability, I adopted the C# naming convention for interfaces, namely, putting a capital 'I' in front of them, a decision i do not feel quite as confident in as I did earlier.
//Note: the calls to message(..) was put in here to help debugging
public class AsyncFileContext : Object{
private int64 offset;
private bool start_read;
private bool read_to_end;
private Factories.IVCardFactory factory;
private File file;
private FileMonitor monitor;
private Gee.Set<IVCard> vcard_buffer;
private IObservableSet<IVCard> _vCards;
public IObservableSet<IVCard> vCards {
owned get{
return this._vCards;
}
}
construct{
//We want to start fileops at the beginning of the file
this.offset = (int64)0;
this.start_read = true;
this.read_to_end = false;
this.vcard_buffer = new Gee.HashSet<IVCard>();
this.factory = new Factories.GenericVCardFactory();
}
public void add_vcard(IVCard card){
//TODO: implement
}
public AsyncFileContext(IObservableSet<IVCard> vcards, string path){
this._vCards = vcards;
this._vCards = IObservableSet.wrap_set<IVCard>(new Gee.HashSet<IVCard>());
this.file = File.new_for_path(path);
this.monitor = file.monitor_file(FileMonitorFlags.NONE, null);
message("1");
//TODO: add connect
this.monitor.changed.connect((file, otherfile, event) => {
if(event != FileMonitorEvent.DELETED){
bool changes_done = event == FileMonitorEvent.CHANGES_DONE_HINT;
Idle.add(() => {
read_file_async.begin(changes_done);
return false;
});
}
});
message("2");
//We don't know that changes are done yet
//TODO: Consider carefully how you want this to work when it is NOT called from an event
Idle.add(() => {
read_file_async.begin(false);
return false;
});
}
//Changes done should only be true if the FileMonitorEvent that triggers the call was CHANGES_DONE_HINT
private async void read_file_async(bool changes_done) throws IOError{
if(!this.start_read){
return;
}
this.start_read = false;
var dis = new DataInputStream(yield file.read_async());
message("3");
//If we've been reading this file, and there's then a change, we assume we need to continue where we let off
//TODO: assert that the offset isn't at the very end of the file, if so reset to 0 so we can reread the file
if(offset > 0){
dis.seek(offset, SeekType.SET);
}
string line;
int vcards_added = 0;
while((line = yield dis.read_line_async()) != null){
message("position: %s".printf(dis.tell().to_string()));
this.offset = dis.tell();
message("4");
message(line);
//if the line is empty, we want to jump to next line, and ignore the input here entirely
if(line.chomp().chug() == ""){
continue;
}
this.factory.add_line(line);
if(factory.vcard_ready){
message("creating...");
this.vcard_buffer.add(factory.create());
vcards_added++;
//If we've read-in and created an entire vcard, it's time to yield
message("Yielding...");
Idle.add(() => {
_vCards.add_all(vcard_buffer);
vcard_buffer.remove_all(_vCards);
return false;
});
Idle.add(read_file_async.callback);
yield;
message("Resuming");
}
}
//IF we expect there will be no more writing, or if we expect that we read ALL the vcards, and did not add any, it's time to go back and read through the whole thing again.
if(changes_done){ //|| vcards_added == 0){
this.offset = 0;
}
this.start_read = true;
}
}
//The main idea in this class is to just bind the IObservableCollection's item_added, item_removed and cleared signals to the items_changed of the ListModel. IObservableCollection is a class I have implemented that merely wraps Gee.Collection, it is unittested, and works as intended
public class VCardListModel : ListModel, Object{
private Gee.List<IVCard> vcard_list;
private IObservableCollection<IVCard> vcard_collection;
public VCardListModel(IObservableCollection<IVCard> vcard_collection){
this.vcard_collection = vcard_collection;
this.vcard_list = new Gee.ArrayList<IVCard>.wrap(vcard_collection.to_array());
this.vcard_collection.item_added.connect((vcard) => {
vcard_list.add(vcard);
int pos = vcard_list.index_of(vcard);
items_changed(pos, 0, 1);
});
this.vcard_collection.item_removed.connect((vcard) => {
int pos = vcard_list.index_of(vcard);
vcard_list.remove(vcard);
items_changed(pos, 1, 0);
});
this.vcard_collection.cleared.connect(() => {
items_changed(0, vcard_list.size, 0);
vcard_list.clear();
});
}
public Object? get_item(uint position){
if((vcard_list.size - 1) < position){
return null;
}
return this.vcard_list.get((int)position);
}
public Type get_item_type(){
return Type.from_name("VikingvCardIVCard");
}
public uint get_n_items(){
return (uint)this.vcard_list.size;
}
public Object? get_object(uint position){
return this.get_item((int)position);
}
}
//The IObservableCollection parsed to this classes constructor, is the one from the AsyncFileContext
public class ContactList : Gtk.ListBox{
private ListModel list_model;
public ContactList(IObservableCollection<IVCard> ivcards){
this.list_model = new VCardListModel(ivcards);
bind_model(this.list_model, create_row_func);
list_model.items_changed.connect(() => {
message("Items Changed!");
base.show_all();
});
}
private Gtk.Widget create_row_func(Object item){
return new ContactRow((IVCard)item);
}
}
Heres the way i 'solved' it.
I'm not particularly proud of this solution, but there are a couple of awful things about the Gtk ListBox, one of them being (and this might really be more of a ListModel issue) if the ListBox is bound to a ListModel, the ListBox will NOT be sortable by using the sort method, and to me at least, that is a dealbreaker. I've solved it by making a class which is basically a List wrapper, which has an 'added' signal and a 'remove' signal. Upon adding an element to the list, the added signal is then wired, so it will create a new Row object and add it to the list box. That way, data is control in a manner Similar to ListModel binding. I can not make it work without calling the ShowAll method though.
private IObservableCollection<IVCard> _ivcards;
public IObservableCollection<IVCard> ivcards {
get{
return _ivcards;
}
set{
this._ivcards = value;
foreach(var card in this._ivcards){
base.prepend(new ContactRow(card));
}
this._ivcards.item_added.connect((item) => {
base.add(new ContactRow(item));
base.show_all();
});
base.show_all();
}
}
Even though this is by no means the best code I've come up with, it works very well.
I have a class ReportConfigurationManager which manages the CRUD operations against a UserReport entity. The two operations of interest are "Get" and "SaveUpdate". In both cases I wrap the operation in a using statement so that the DbContext is disposed at the end of the query.
Now eventually these methods will form part of a WCF service, but they may also be called internally within the service. My present difficulties are with getting a set of Unit Tests to work which call the ReportConfigurationManager directly.
I can create a new UserReport and save it (this took me a while to solve as the entity has several nested objects which already exist in the database - I needed to "Attach" each of these in turn to the context before calling Add on the UserReport in order to get it to save correctly.
My issues now are with Updates.
Despite having
context.Configuration.ProxyCreationEnabled = false;
context.Configuration.AutoDetectChangesEnabled = false;
on ALL methods which use the ReportConfigurationManager, when I came to attach a UserReport, it failed with the classic "an object with the same key already exists in the ObjectStateManager" (I thought disabling Change Tracking was meant to handle this?).
So now I have switched to using the following code which I found here
public UserReport SaveUpdateUserReport(UserReport userReport)
{
using (var context = new ReportDataEF())
{
context.Configuration.ProxyCreationEnabled = false;
context.Configuration.AutoDetectChangesEnabled = false;
if (userReport.Id > 0)
{
{
UserReport oldReport = context.UserReports.Where(ur => ur.Id == userReport.Id).FirstOrDefault();
context.Entry(oldReport).CurrentValues.SetValues(userReport);
}
}
else
{
//Need to attach everything to prevent EF trying to create duplicates in the database
context.ReportTopTypes.Attach(userReport.ReportTopType);
context.ReportWindows.Attach(userReport.ReportWindow);
context.ReportSortOptions.Attach(userReport.ReportSortOption);
foreach (var col in userReport.ReportColumnGroups)
{
context.ReportColumnGroups.Attach(col);
}
context.ReportTemplates.Attach(userReport.ReportTemplate);
//just add the new data
context.UserReports.Add(userReport);
}
context.SaveChanges();
}
return userReport;
}
My concern is that my code seems laborious - I need to get a copy of the old object before I can save the updated copy? And I'm not convinced by my Save New logic either.
So is this approach correct, or is there a better way of writing the above?
Further details of other stuff going on:
Because I'll be sending the object graphs over WCF. I've implemented Eager Loading:
public static DbQuery<ReportTemplate> IncludeAll(this DbQuery<ReportTemplate> self)
{
return self
.Include("ReportColumnGroups.ReportColumns.ReportColumnType")
.Include("ReportColumnGroups.ReportColumnType")
.Include("ReportSortOptions.ReportSortColumns.ReportColumn.ReportColumnType")
.Include("ReportSortOptions.ReportSortColumns.ReportSortType");
}
public static DbQuery<UserReport> IncludeAll(this DbQuery<UserReport> self)
{
return self
.Include("ReportTemplate")
.Include("ReportTopType")
.Include("ReportWindow")
.Include("ReportSortOption.ReportSortColumns.ReportColumn.ReportColumnType")
.Include("ReportSortOption.ReportSortColumns.ReportSortType")
.Include("ReportColumnGroups.ReportColumns.ReportColumnType")
.Include("ReportColumnGroups.ReportColumnType");
}
public static DbQuery<ReportSortOption> IncludeAll(this DbQuery<ReportSortOption> self)
{
return self
.Include("ReportSortColumns.ReportColumn.ReportColumnType")
.Include("ReportSortColumns.ReportSortType");
}
public static DbQuery<ReportColumnGroup> IncludeAll(this DbQuery<ReportColumnGroup> self)
{
return self
.Include("ReportColumn.ReportColumnType")
.Include("ReportColumnType");
}
public static DbQuery<ReportColumn> IncludeAll(this DbQuery<ReportColumn> self)
{
return self
.Include("ReportColumnType");
}
public static DbQuery<ReportSortColumn> IncludeAll(this DbQuery<ReportSortColumn> self)
{
return self
.Include("ReportColumn.ReportColumnType")
.Include("ReportSortType");
}
I have a set of static, cached data that I obtain as follows:
using (var context = new ReportDataEF())
{
context.Configuration.ProxyCreationEnabled = false;
context.Configuration.AutoDetectChangesEnabled = false;
reportConfigurationData = new ReportingMetaData()
{
WatchTypes = context.WatchTypes.ToList(),
ReportTemplates = context.ReportTemplates.IncludeAll().ToList(),
ReportTopTypes = context.ReportTopTypes.ToList(),
ReportWindows = context.ReportWindows.ToList(),
ReportSortOptions =
context.ReportSortOptions.IncludeAll().ToList()
};
}
and I retrieve UserReports as follows:
public UserReport GetUserReport(int userReportId)
{
using (var context = new ReportDataEF())
{
context.Configuration.ProxyCreationEnabled = false;
context.Configuration.AutoDetectChangesEnabled = false;
var visibleReports =
context.UserReports.IncludeAll().Where(ur => ur.Id == userReportId).FirstOrDefault();
return visibleReports;
}
}
The test I am concerned with gets an existing UserReport from the DB, Updates its ReportTemplate and ReportColumnGroups properties with objects from the static data class and then attempts to save the updated UserReport.
Using the code from Ladislav's answer, this fails when I try to attach the UserReport, presumably because one of the objects I've attached to it, already exists in the database.
Yes there is another way. First think you should know is that EF doesn't support partially attached object graphs so both Attach and Add have side effects to attach or add all entities in the graph which are not yet tracked by the context. This will simplify your insertion code a lot.
public UserReport SaveUpdateUserReport(UserReport userReport)
{
using (var context = new ReportDataEF())
{
context.Configuration.ProxyCreationEnabled = false;
context.Configuration.AutoDetectChangesEnabled = false;
// Now all entities in the graph are attached in unchanged state
context.ReportTopTypes.Attach(userReport);
if (userReport.Id > 0 &&
context.UserReports.Any(ur => ur.Id == userReport.Id))
{
context.Entry(userReport).State = EntityState.Modified;
}
else
{
context.Entry(userReport).State = EntityState.Added;
}
context.SaveChanges();
}
return userReport;
}
This is equivalent to your original code. You don't load user report again - you just check its existence in DB. This code has a lot of problems - for example if you changed any other related object it will not be persisted to database because currently its state is Unchanged. It can be even more complicated if you need to change relations.
I have a requirement in which i wanna filter the textbox value, that is should remove the bad words entered by the user. Once the user enters the bad words and click on submit button, action is invoked. Somewhere in the model(any place) i should be able to remove the bad words and rebind the filtered value back to the model.
How can i do this?
If you can update the solution to MVC 3 the solution is trivial. Just implement the word check in a controller and then apply the RemoteAttribute on the property that should be validated against bad words. You will get an unobtrusive ajax check and server side check with just one method and one attribute. Example:
public class YourModel
{
[Remote("BadWords", "Validation")]
public string Content { get; set; }
}
public class ValidationController
{
public JsonResult BadWords(string content)
{
var badWords = new[] { "java", "oracle", "webforms" };
if (CheckText(content, badWords))
{
return Json("Sorry, you can't use java, oracle or webforms!", JsonRequestBehavior.AllowGet);
}
return Json(true, JsonRequestBehavior.AllowGet);
}
private bool CheckText(string content, string[] badWords)
{
foreach (var badWord in badWords)
{
var regex = new Regex("(^|[\\?\\.,\\s])" + badWord + "([\\?\\.,\\s]|$)");
if (regex.IsMatch(content)) return true;
}
return false;
}
}
I'm just getting to grips with custom validation attributes, and I'm trying to write a custom validation attirbute which will be placed at class level to validate against multiple properties of my model.
I can access all properties on my model, and I want to be able to check for multiple conditions in my IsValid overload, and report on them, having different error messages as follows (simplistic example).
public override bool IsValid(object value)
{
var model = (MyObject) value;
//if this value is set, I don't want to do anything other checks
if (model.Prop3)
{
return true;
}
if (model.Prop1 == "blah" && model.Prop2 == 1)
{
ErrorMessage = "you can't enter blah if prop 2 equals 1";
return false;
}
if(model.Prop1 == "blah blah" && model.Prop2 == 2)
{
ErrorMessage = "you can't enter blah blah if prop 2 equals 2";
return false;
}
return true;
}
But when I do this I get an exception on the first time ErrorMessage is referenced "Cannot set property more than once.
Now I could split up my custom attribute into multiple custom attributes, but hoped there would be a way to do it in one, otherwise, I'll be repeating my "catch all" in each
//if this value is set, I don't want to do anything other checks
if (model.Prop3)
{
return true;
}
I've had a search already, but couldn't find anything, so apologies if I am missing anything obvious.
thanks in advance!
In MVC4 you can override IsValid to return different messages as the ValidationResult
public class StrongPasswordAttribute : ValidationAttribute
{
protected override ValidationResult IsValid(object value, ValidationContext context)
{
if (value == null)
return new ValidationResult("Password is required");
var val = value.ToString();
if (!Regex.Match(val, #"^(?=.*[a-z]).{0,}$").Success)
{
return new ValidationResult("Password must contain at least one lower case letter");
}
if (!Regex.Match(val, #"^(?=.*[A-Z]).{0,}$").Success)
{
return new ValidationResult("Password must contain at least one UPPER case letter");
}
if (!Regex.Match(val, #"^(?=.*\d).{0,}$").Success)
{
return new ValidationResult("Password must contain at least one number");
}
return ValidationResult.Success;
}
}
Interesting question! I can think of two work-arounds to this. So not proper solutions based on what you want but they might help to re-use your code. Cant you create a CustomAttribute abstract class called MyCustomAttribute (or something) that overrides IsValid in the following way:
public override bool IsValid(object value)
{
var model = (MyObject) value;
//if this value is set, I don't want to do anything other checks
if (model.Prop3)
{
return true;
}
CustomValidate(model);
}
CustomValidate(MyObject model) is your abstract method then, you can write multiple custom attribute classes that extend MyCustomAttribute and purely need to implement the validation logic for A particular scenario.
So you can have two classes:
public class BlahCustomAttribute : MyCustomAttribute
{
public override Boolean CustomValidate(MyObject obj)
{
if (model.Prop1 == "blah" && model.Prop2 == 1)
{
ErrorMessage = "you can't enter blah if prop 2 equals 1";
return false;
}
}
}
public class BlahBlahCustomAttribute : MyCustomAttribute
{
public override Boolean CustomValidate(MyObject obj)
{
if (model.Prop1 == "blah" && model.Prop2 == 1)
{
ErrorMessage = "you can't enter blah blah if prop 2 equals 1";
return false;
}
}
}
Hope this helps - not exactly what you wanted but will do the job and its clean as well.
The other solution is to comma-separate the error messages in the ErrorMessage property and handle it in the front-end (but I would go with the first approach).
In Asp.net MVC the url structure goes like
http://example.com/{controller}/{action}/{id}
For each "controller", say http://example.com/blog, there is a BlogController.
But my {controller} portion of the url is not decided pre-hand, but it is dynamically determined at run time, how do I create a "dynamic controller" that maps anything to the same controller which then based on the value and determines what to do?
Same thing with {action}, if the {action} portion of my url is also dynamic, is there a way to program this scenario?
Absolutely! You'll need to override the DefaultControllerFactory to find a custom controller if one doesn't exist. Then you'll need to write an IActionInvoker to handle dynamic action names.
Your controller factory will look something like:
public class DynamicControllerFactory : DefaultControllerFactory
{
private readonly IServiceLocator _Locator;
public DynamicControllerFactory(IServiceLocator locator)
{
_Locator = locator;
}
protected override Type GetControllerType(string controllerName)
{
var controllerType = base.GetControllerType(controllerName);
// if a controller wasn't found with a matching name, return our dynamic controller
return controllerType ?? typeof (DynamicController);
}
protected override IController GetControllerInstance(Type controllerType)
{
var controller = base.GetControllerInstance(controllerType) as Controller;
var actionInvoker = _Locator.GetInstance<IActionInvoker>();
if (actionInvoker != null)
{
controller.ActionInvoker = actionInvoker;
}
return controller;
}
}
Then your action invoker would be like:
public class DynamicActionInvoker : ControllerActionInvoker
{
private readonly IServiceLocator _Locator;
public DynamicActionInvoker(IServiceLocator locator)
{
_Locator = locator;
}
protected override ActionDescriptor FindAction(ControllerContext controllerContext,
ControllerDescriptor controllerDescriptor, string actionName)
{
// try to match an existing action name first
var action = base.FindAction(controllerContext, controllerDescriptor, actionName);
if (action != null)
{
return action;
}
// #ray247 The remainder of this you'd probably write on your own...
var actionFinders = _Locator.GetAllInstances<IFindAction>();
if (actionFinders == null)
{
return null;
}
return actionFinders
.Select(f => f.FindAction(controllerContext, controllerDescriptor, actionName))
.Where(d => d != null)
.FirstOrDefault();
}
}
You can see a lot more of this code here. It's an old first draft attempt by myself and a coworker at writing a fully dynamic MVC pipeline. You're free to use it as a reference and copy what you want.
Edit
I figured I should include some background about what that code does. We were trying to dynamically build the MVC layer around a domain model. So if your domain contained a Product class, you could navigate to products\alls to see a list of all products. If you wanted to add a product, you'd navigate to product\add. You could go to product\edit\1 to edit a product. We even tried things like allowing you to edit properties on an entity. So product\editprice\1?value=42 would set the price property of product #1 to 42. (My paths might be a little off, I can't recall the exact syntax anymore.) Hope this helps!
After a little more reflection, there may be a bit simpler way for you to handle the dynamic action names than my other answer. You'll still need to override the default controller factory. I think you could define your route like:
routes.MapRoute("Dynamic", "{controller}/{command}/{id}", new { action = "ProcessCommand" });
Then on your default/dynamic controller you'd have
public ActionResult ProcessCommand(string command, int id)
{
switch(command)
{
// whatever.
}
}
You need to write your own IControllerFactory (or perhaps derive from DefaultControllerFactory) and then register it with ControllerBuilder.
Iam working with it in .Core but i'll share it's MVC version for all, after that i will share the core version
case OwnerType.DynamicPage:
var dp = mediator.Handle(new Domain.DynamicPages.DynamicPageDtoQuery { ShopId = ShopId, SeoId = seoSearchDto.Id }.AsSingle());
if (dp != null)
{
return GetDynamicPage(dp.Id);
}
break;
// some codes
private ActionResult GetDynamicPage(int id)
{
var routeObj = new
{
action = "Detail",
controller = "DynamicPage",
id = id
};
var bController = DependencyResolver.Current.GetService<DynamicPageController>();
SetControllerContext(bController, routeObj);
return bController.Detail(id);
}
// and
private void SetControllerContext(ControllerBase controller, object routeObj)
{
RouteValueDictionary routeValues = new RouteValueDictionary(routeObj);
var vpd = RouteTable.Routes["Default"].GetVirtualPath(this.ControllerContext.RequestContext, routeValues);
RouteData routeData = new RouteData();
foreach (KeyValuePair<string, object> kvp in routeValues)
{
routeData.Values.Add(kvp.Key, kvp.Value);
}
foreach (KeyValuePair<string, object> kvp in vpd.DataTokens)
{
routeData.DataTokens.Add(kvp.Key, kvp.Value);
}
routeData.Route = vpd.Route;
if (routeData.RouteHandler == null)
routeData.RouteHandler = new MvcRouteHandler();
controller.ControllerContext = new ControllerContext(this.ControllerContext.HttpContext, routeData, controller);
}