#{
var grid = new WebGrid(Model.Auctions, rowsPerPage: Model.PagingInfo.ItemsPerPage, defaultSort: "AddedDate");
}
#grid.GetHtml(
columns: grid.Columns(
**grid.Column(columnName: "", header: "Type", format: (auction) => AuctionListViewModel.GetAuctionType(auction)),**
grid.Column(columnName: "OwnerReference", header: "Owner reference")
)
);
public class AuctionListViewModel
{
public IEnumerable<Auction> Auctions { get; set; }
public IEnumerable<Item> Items { get; set; }
public PagingInfo PagingInfo { get; set; }
public string Title { get; set; }
public string Action { get; set; }
public static string GetAuctionType(Auction auction)
{
var type = string.Empty;
if (auction is LubAuction)
{
type = "Lowest unique wins";
}
else if (auction is EsfAuction)
{
type = "Highest wins";
}
return type;
}
}
With the above view code and model, get the following error on the line marked in bold, why is this?
The best overloaded method match for 'UI.Models.AuctionListViewModel.GetAuctionType(UI.AuctionService.Auction)' has some invalid arguments
In the grid.Column method's format parameter's parameter (in your case auction) you get the actual item (an Auction) but it's wrapped into a dynamic wrapper called WebGridRow.
You can use your properties on this wrapper and it delegates to the actual item e.g: auction.Title will work, but if you want to get the whole item (the Auction) you need to use the Value property of the WebGridRow.
format: auction =>
uctionListViewModel.GetAuctionType(((WebGridRow)auction).Value)
Due to the dynamic (weak) typing of the WebGrid helper you need a cast:
grid.Column(
columnName: "",
header: "Type",
format: (auction) => AuctionListViewModel.GetAuctionType((Auction)auction.Value)
)
I would recommend you using better grid helpers such as MvcContrib Grid and Telerik Grid which will give you strong typing and compile time safety.
Related
I stored the objects of the following classes in a ravendb database:
public class Continent
{
public string Id { get; set; }
public string Name { get; set; }
public List<Country> Countries { get; set; }
}
public class Country
{
public string Name { get; set; }
public List<Province> Provinces { get; set; }
}
public class Province
{
public string Name { get; set; }
public List<City> Cities { get; set; }
}
public class City
{
public string Name { get; set; }
public string Address { get; set; }
}
I want to write a method that searches Continents having a specific city. The latter is a parameter of my method. In this method, I want to execute a dynamic query like the following: query= session.Query().Where(ConditionOnTheSearchedCity). But I can not formulate the Expression "ConditionOnTheSearchedCity" because I can not iterate till the Name of each City. In fact, to create an expression based on the Name of the City, I've tried the following which is not working:
ParameterExpression parameterExpression = Expression.Parameter(typeof(Continent), "p");
Expression NameExpression = Expression.PropertyOrField(
Expression.PropertyOrField(
Expression.PropertyOrField(
Expression.PropertyOrField(parameterExpression, "Countries"), "Provinces"),
"Cities"),
"Name");
Can you please help me? Thanks in advance
Why are you going to all the trouble of dynamically building Linq?
Why not just use the RavenDB's DocumentQuery API which allows you to easily build queries dynamically?
As I mentioned in the comments, the question is too broad, so I'll give you just a starting point by providing an example. For more information, take a look at How to: Use Expression Trees to Build Dynamic Queries.
Let have a parameter string cityName and want a filter like this
Expression<Func<Continent, bool>> filter = continent =>
continent.Countries.Any(country =>
country.Provinces.Any(province =>
province.Cities.Any(city => city.Name == cityName)));
It can be build dynamically like this
var city = Expression.Parameter(typeof(City), "city");
var cityCondition = Expression.Equal(Expression.PropertyOrField(city, "Name"), Expression.Constant(cityName));
var province = Expression.Parameter(typeof(Province), "province");
var provinceCondition = Expression.Call(
typeof(Enumerable), "Any", new[] { city.Type },
Expression.PropertyOrField(province, "Cities"),
Expression.Lambda(cityCondition, city));
var country = Expression.Parameter(typeof(Country), "country");
var countryCondition = Expression.Call(
typeof(Enumerable), "Any", new[] { province.Type },
Expression.PropertyOrField(country, "Provinces"),
Expression.Lambda(provinceCondition, province));
var continent = Expression.Parameter(typeof(Continent), "continent");
var continentCondition = Expression.Call(
typeof(Enumerable), "Any", new[] { country.Type },
Expression.PropertyOrField(continent, "Countries"),
Expression.Lambda(countryCondition, country));
var filter = Expression.Lambda<Func<Continent, bool>>(continentCondition, continent);
I'm having hard time understanding how to convert an Enum value to it's corresponding name. My model is as follows:
public class CatalogRule
{
public int ID { get; set; }
[Display(Name = "Catalog"), Required]
public int CatalogID { get; set; }
[Display(Name = "Item Rule"), Required]
public ItemType ItemRule { get; set; }
public string Items { get; set; }
[Display(Name = "Price Rule"), Required]
public PriceType PriceRule { get; set; }
[Display(Name = "Value"), Column(TypeName = "MONEY")]
public decimal PriceValue { get; set; }
[Display(Name = "Exclusive?")]
public bool Exclude { get; set; }
}
public enum ItemType
{
Catalog,
Category,
Group,
Item
}
public enum PriceType
{
Catalog,
Price_A,
Price_B,
Price_C
}
A sample result from .net API:
[
{
$id: "1",
$type: "XYZ.CMgr.Models.CatalogRule, XYZ.CMgr",
ID: 1,
CatalogID: 501981,
ItemRule: 0,
Items: "198",
PriceRule: 1,
PriceValue: 0.5,
Exclude: false
},
{
$id: "2",
$type: "XYZ.CMgr.Models.CatalogRule, XYZ.CMgr",
ID: 2,
CatalogID: 501981,
ItemRule: 2,
Items: "9899",
PriceRule: 2,
PriceValue: 10.45,
Exclude: false
}
]
So in this example, I need to get Catalog for results[0].ItemRule & Price A for results[0].PriceRule. How can I accomplish this in BreezeJS??
This is easy to do in ASP.NET Web API, because it is an out-of-box feature in the default JSON serializer (Json.NET).
To see strings instead of enum numbers in JSON, just add an instance of StringEnumConverter to JSON serializer settings during app init:
var jsonFormatter = GlobalConfiguration.Configuration.Formatters.JsonFormatter;
jsonFormatter.SerializerSettings.Converters.Add(new Newtonsoft.Json.Converters.StringEnumConverter());
UPDATE: Yep, you right, this is not help with Breeze.js. Ok, you can anyway do a little magic to make enums work like strings (while new version with fix is not released).
Create a custom ContextProvider which updates all integer enum values in metadata to strings. Here it is:
public class StringEnumEFContextProvider<T> : EFContextProvider<T>
where T : class, new()
{
protected override string BuildJsonMetadata()
{
XDocument xDoc;
if (Context is DbContext)
{
xDoc = GetCsdlFromDbContext(Context);
}
else
{
xDoc = GetCsdlFromObjectContext(Context);
}
var schemaNs = "http://schemas.microsoft.com/ado/2009/11/edm";
foreach (var enumType in xDoc.Descendants(XName.Get("EnumType", schemaNs)))
{
foreach (var member in enumType.Elements(XName.Get("Member", schemaNs)))
{
member.Attribute("Value").Value = member.Attribute("Name").Value;
}
}
return CsdlToJson(xDoc);
}
}
And use it instead of EFContextProvider in your Web API controllers:
private EFContextProvider<BreezeSampleContext> _contextProvider =
new StringEnumEFContextProvider<BreezeSampleContext>();
This works well for me with current Breeze.js version (1.1.3), although I haven't checked other scenarios, like validation...
UPDATE: To fix validation, change data type for enums in breeze.[min|debug].js, manually (DataType.fromEdmDataType function, dt = DataType.String; for enum) or replace default function during app init:
breeze.DataType.fromEdmDataType = function (typeName) {
var dt = null;
var parts = typeName.split(".");
if (parts.length > 1) {
var simpleName = parts[1];
if (simpleName === "image") {
// hack
dt = DataType.Byte;
} else if (parts.length == 2) {
dt = DataType.fromName(simpleName);
if (!dt) {
if (simpleName === "DateTimeOffset") {
dt = DataType.DateTime;
} else {
dt = DataType.Undefined;
}
}
} else {
// enum
dt = DataType.String; // THIS IS A FIX!
}
}
return dt;
};
Dirty, dirty hacks, I know... But that's the solution I found
There will be a new release out in the next few days where we "change" breeze's enum behavior ( i.e. break existing code with regards to enums). In the new release enums are serialized and queried by their .NET names instead of as integers. I will post back here when the new release is out.
I have been struggling with this for several days. I need to populate a dropdownlistfor with genres.
My MovieRepository to grab the genres:
public IQueryable<Movies> MoviesAndGenres
{
get { return db.Movies.Include(m => m.parentGenre); }
}
My movie model
public virtual Genres parentGenre { get; set; }
Genre Model:
public class Genres
{
public Genres()
{
this.movies = new HashSet<Movies>();
}
[Key]
public int genreId { get; set; }
[Required(ErrorMessage = "A genre name is required")]
[StringLength(25)]
public String genreName { get; set; }
public ICollection<Movies> movies { get; set; }
}
I am trying to pass in the genres with a select list, but I am getting a LINQ to Entities does not recognize the System.String To String() Method, and this method cannot be translated to a stored expression.
Movies Controller, addMovie action:
ViewBag.Genres = movieRepository.MoviesAndGenres.Select(m => new SelectListItem
{
Text = m.parentGenre.genreName,
Value = m.parentGenre.genreId.ToString()
}).ToList();
return View();
View:
#Html.DropDownListFor(m => m.parentGenre, (SelectList)ViewBag.Genres)
Any help would be greatly appreciated!
Update:
Repository:
public IQueryable<Genres> MoviesAndGenres
{
get { return db.Genres; }
}
Controller:
var x = movieRepository.MoviesAndGenres.Select(m => new
{
Text = m.genreName,
Value = m.genreId
});
ViewBag.Genres = new SelectList(x);
return View();
View:
#Html.DropDownListFor(m => m.parentGenre, (SelectList)ViewBag.Genres)
Since you're retrieving all of the records anyways, you can just do this.
ViewBag.Genres = movieRepository.MoviesAndGenres.AsEnumerable()
.Select(m => new SelectListItem
{
Text = m.parentGenre.genreName,
Value = m.parentGenre.genreId.ToString()
});
You would also need to change your view to:
#Html.DropDownListFor(m => m.parentGenre, new SelectList(ViewBag.Genres))
Actually, a better approach would probably be this, since then it only retrieves the specific columns you need:
var x = movieRepository.MoviesAndGenres.Select(m => new
{
Text = m.parentGenre.genreName,
Value = m.parentGenre.genreId
});
ViewBag.Genres = new SelectList(x)
Also, the ToList() is no longer required because it's already in a an immediate state.
I am trying to get four cascading dropdowns using knockout.js:
Search Criteria
Sub Criteria
Value
State
I was able to get the first cascade going (but not the others due to databinding issues) by using code from the following link:
http://blogs.msdn.com/b/thebeebs/archive/2011/12/01/price-calculator.aspx
The data for these dropdowns is being returned to my razor viewpage as an IEnumrable of SearchCriterion from an MVC view using ViewBag.CriteriaData variable. The code for my classes is as follows:
public class SearchCriterion
{
public string Text { get; set; }
public string Value { get; set; }
public List<SubCriterion> SubCriteria { get; set; }
}
public class SubCriterion
{
public string SearchCriterionValue { get; set; }
public string Text { get; set; }
public string Value { get; set; }
public List<ColumnValue> ColumnValues { get; set; }
}
public class ColumnValue
{
public string SearchCriterionValue { get; set; }
public string SubCriterionValue { get; set; }
public string Text { get; set; }
public string Value { get; set; }
public IEnumerable<StateValue> StateValues { get; set; }
}
public class StateValue
{
public string SearchCriterionValue { get; set; }
public string SubCriterionValue { get; set; }
public string ColumnValue { get; set; }
public IEnumerable<int> InputStateIds { get; set; }
public IEnumerable<int> OutputStateIds { get; set; }
public int SelectedInputStateId { get; set; }
public int SelectedOutputStateId { get; set; }
public string Text { get; set; }
public string Value { get; set; }
}
The issues I am facing are in the following portions of the .cshtml code:
What do I specify in this template for the other two dropdowns. e.g. the third dropdown needs to be bound to ColumnValue.Value (ColumnValue is part of SubCriterion)
<script id='criteriaRowTemplate' type='text/html'>
<tr>
<td><select data-bind='options: criteriaData, optionsText: "Text", optionsCaption: "Search Criterion", value: SearchCriterion' /></td>
<td><select data-bind='visible: SearchCriterion, options: SearchCriterion() ? SearchCriterion().SubCriteria : null, optionsText: "Text", optionsCaption: "Sub Criterion", value: SubCriterion' /></td>
<td><select data-bind='visible: SubCriterion, options: SubCriterion() ? SubCriterion().ColumnValues : null, optionsText: "Text", optionsCaption: "Column Value", value: ColumnValue'/></td>
<td><select data-bind='visible: ColumnValue, options: ColumnValue() ? ColumnValue().StateValues : null, optionsText: "Text", optionsCaption: "State", value: StateValue'/></td>
<td><button data-bind='click: function() { viewModel.removeLine($data) }'>Remove</button></td>
</tr>
</script>
Is this correct?
var CriteriaLine = function() {
this.SearchCriterion = ko.observable();
this.SubCriterion = ko.observable();
this.ColumnValue = ko.observable();
this.StateValue = ko.observable();
// Whenever the Search Criteria changes, reset the Sub Criteria selection
this.SearchCriterion.subscribe(function() { this.SubCriterion(undefined); }.bind(this));
this.SubCriterion.subscribe(function() { this.ColumnValue(undefined); }.bind(this));
this.ColumnValue.subscribe(function() { this.StateValue(undefined); }.bind(this));
};
How do I map the complete C# object with the Javascript object? It works if we just have the first two dropdowns:
// Create a Javascript object object with the same property names as the C# object
var dataToSearch = $.map(this.lines(), function (line) { return line.StateValue() ? line.StateValue() : undefined; });
var SearchObject = new function () {
this.StateValues = dataToSearch;
};
// Convert the object to JSON
var searchCriteria = JSON.stringify(SearchObject);
Does anything need to change here for the binding?
// Apply the data from the server to the variable
var criteriaData = #Html.Raw(#Json.Encode(ViewBag.CriteriaData));
var viewModel = new Criteria();
ko.applyBindings(viewModel, document.getElementById("criteriaDiv"));
EDIT:
I am now able to populate the cascading dropdowns (updated code above). Now I have 4 columns, each column having one of the dropdowns. I also have 1...n number of rows being added dynamically by using Knockoutjs. So, the user can now select values from these dropdowns and add more rows of dropdowns if he wants. The only thing remaining is to return the values that the user selects for the dropdowns to the controller(point 3 above). I am not sure how I can do that. Any help would be appreciated.
EDIT 2:
Added working code for Item # 3 and modified the ColumnValue and StateValue classes.
I'm not sure I fully understand your question, but I'm going to take a whack at it anyway :). I think you're looking for a way to "validate" if it is in fact time to allow the next drop down to be active?
If so, you could approach it from a standpoint of Computed Observables. Basically, you would bind each of your dropdowns to a computed value which is derived from the previous dependencies.
Let me write fiddle and I'll show you :)
OK, give this a shot...sorry for the delay...http://jsfiddle.net/farina/ZNBcM/3/
I update the answer, Hope, it will help new Comers.
Methods for Binding Hierarchical Dropdowns using Knockout JS in MVC
Here you can find the good example .
I am trying to render a Partial from within a System.Web.Helpers.WebGrid
my model class looks like this:
class GameInfo
{
public List<AppUser> Team1 { get; set; }
public List<AppUser> Team2 { get; set; }
// and more properties
}
class AppUser
{
public string PictureUrl { get; set; }
public string ProfileUrl { get; set; }
public long GamesWon { get; set; }
public long GamesLost { get; set; }
public int Points { get; set; }
// and more properties
}
I want my GridView to show a list of GameInfo's in my grid view.
What is turning out be to be tougher than expected is rendering the Teams (List).
To stay DRY I created a partial view to render a Team (_Team.cstml).
This is my razor code:
#if (Model != null)
{
var webgrid = new WebGrid(source: Model.Games,
rowsPerPage: 10);
<div id="grid">
#webgrid.GetHtml(
columns: webgrid.Columns(
webgrid.Column(header: "Score", format: #<text>#item.Score1/#item.Score1</text>),
webgrid.Column(header: "Team 1", format: (item) =>
{
return "hello sb"; // this line works!
//return Html.Partial("_Team", item.Team1); // this gives an error
})
)
)
</div>
}
Any idea how I can get this to work?
Thank you!
In case someone else runs into this, I managed to solve it this morning.
This works:
webgrid.Column(header: "Team 1", format: (item) =>
{
List<Cuarenta.Web.Models.AppUser> team = ((Cards.Cloud.WebRole.Admin.GameInfo)item.Value).Team1;
return Html.Partial("_Team", team);
})