I was going to practice how to create Inventory, but it seems it won't read the parameter from the other script. I'm working on my training based on my tutorial, here's how the code goes:
public class ItemCatalogue : MonoBehaviour
{
public Items[] AvailableItems;
public Text DisplayArray;
public void GetItem()
{
Items item = AvailableItems[Random.Range(0, AvailableItems.Length)];
InventoryCatalogue.Instance.AddMaterialToCatalogue(new ItemStack(FoodMaterial, amount));//weird, the parameter doesn't exist
DisplayArray.text = item.name;
}
// Use this for initialization
void Start ()
{
}
// Update is called once per frame
void Update ()
{
}
}
And here's the other script:
[System.Serializable]
public class ItemStack
{
public Items FoodMaterial;
public int amount;
public ItemStack(Items FoodMaterial, int amount) //here's the parameter
{
this.FoodMaterial = FoodMaterial;
this.amount = amount;
}
}
i didn't expect anything because i haven't finished the tutorial. anybody know why?
well in
InventoryCatalogue.Instance.AddMaterialToCatalogue(new ItemStack(FoodMaterial, amount));
you call
new ItemStack(FoodMaterial, amount)
with the parameters FoodMaterial, amount but your ItemCatalogue class nor the method GetItem contains any variables/fields/properties with those names.
You rather have to pass some values in there like e.g.
// I don't know what you want to pass in as amount
new ItemStack(item, 1)
so
Items item = AvailableItems[Random.Range(0, AvailableItems.Length)];
InventoryCatalogue.Instance.AddMaterialToCatalogue(new ItemStack(item, 1));
I need to get differences between two IEnumerable. I wrote extension method for it. But as you can see, it has performance penalties. Anyone can write better version of it?
EDIT
After first response, I understand that I could not explain well. I'm visiting both arrays three times. This is performance penalty. It must be a single shot.
PS: Both is optional :)
public static class LinqExtensions
{
public static ComparisonResult<T> Compare<T>(this IEnumerable<T> source, IEnumerable<T> target)
{
// Looping three times is performance penalty!
var res = new ComparisonResult<T>
{
OnlySource = source.Except(target),
OnlyTarget = target.Except(source),
Both = source.Intersect(target)
};
return res;
}
}
public class ComparisonResult<T>
{
public IEnumerable<T> OnlySource { get; set; }
public IEnumerable<T> OnlyTarget { get; set; }
public IEnumerable<T> Both { get; set; }
}
Dependig on the use-case, this might be more efficient:
public static ComparisonResult<T> Compare<T>(this IEnumerable<T> source, IEnumerable<T> target)
{
var both = source.Intersect(target).ToArray();
if (both.Any())
{
return new ComparisonResult<T>
{
OnlySource = source.Except(both),
OnlyTarget = target.Except(both),
Both = both
};
}
else
{
return new ComparisonResult<T>
{
OnlySource = source,
OnlyTarget = target,
Both = both
};
}
}
You're looking for an efficient full outer join.
Insert all items into a Dictionary<TKey, Tuple<TLeft, TRight>>. If a given key is not present, add it to the dictionary. If it is present, update the value. If the "left member" is set, this means that the item is present in the left source collection (you call it source). The opposite is true for the right member. You can do that using a single pass over both collections.
After that, you iterate over all values of this dictionary and output the respective items into one of three collections, or you just return it as an IEnumerable<Tuple<TLeft, TRight>> which saves the need for result collections.
I realize that a lot of questions have been asked relating to full text search and Entity Framework, but I hope this question is a bit different.
I am using Entity Framework, Code First and need to do a full text search. When I need to perform the full text search, I will typically have other criteria/restrictions as well - like skip the first 500 rows, or filter on another column, etc.
I see that this has been handled using table valued functions - see http://sqlblogcasts.com/blogs/simons/archive/2008/12/18/LINQ-to-SQL---Enabling-Fulltext-searching.aspx. And this seems like the right idea.
Unfortunately, table valued functions are not supported until Entity Framework 5.0 (and even then, I believe, they are not supported for Code First).
My real question is what are the suggestions for the best way to handle this, both for Entity Framework 4.3 and Entity Framework 5.0. But to be specific:
Other than dynamic SQL (via System.Data.Entity.DbSet.SqlQuery, for example), are there any options available for Entity Framework 4.3?
If I upgrade to Entity Framework 5.0, is there a way I can use table valued functions with code first?
Thanks,
Eric
Using interceptors introduced in EF6, you could mark the full text search in linq and then replace it in dbcommand as described in http://www.entityframework.info/Home/FullTextSearch:
public class FtsInterceptor : IDbCommandInterceptor
{
private const string FullTextPrefix = "-FTSPREFIX-";
public static string Fts(string search)
{
return string.Format("({0}{1})", FullTextPrefix, search);
}
public void NonQueryExecuting(DbCommand command, DbCommandInterceptionContext<int> interceptionContext)
{
}
public void NonQueryExecuted(DbCommand command, DbCommandInterceptionContext<int> interceptionContext)
{
}
public void ReaderExecuting(DbCommand command, DbCommandInterceptionContext<DbDataReader> interceptionContext)
{
RewriteFullTextQuery(command);
}
public void ReaderExecuted(DbCommand command, DbCommandInterceptionContext<DbDataReader> interceptionContext)
{
}
public void ScalarExecuting(DbCommand command, DbCommandInterceptionContext<object> interceptionContext)
{
RewriteFullTextQuery(command);
}
public void ScalarExecuted(DbCommand command, DbCommandInterceptionContext<object> interceptionContext)
{
}
public static void RewriteFullTextQuery(DbCommand cmd)
{
string text = cmd.CommandText;
for (int i = 0; i < cmd.Parameters.Count; i++)
{
DbParameter parameter = cmd.Parameters[i];
if (parameter.DbType.In(DbType.String, DbType.AnsiString, DbType.StringFixedLength, DbType.AnsiStringFixedLength))
{
if (parameter.Value == DBNull.Value)
continue;
var value = (string)parameter.Value;
if (value.IndexOf(FullTextPrefix) >= 0)
{
parameter.Size = 4096;
parameter.DbType = DbType.AnsiStringFixedLength;
value = value.Replace(FullTextPrefix, ""); // remove prefix we added n linq query
value = value.Substring(1, value.Length - 2);
// remove %% escaping by linq translator from string.Contains to sql LIKE
parameter.Value = value;
cmd.CommandText = Regex.Replace(text,
string.Format(
#"\[(\w*)\].\[(\w*)\]\s*LIKE\s*#{0}\s?(?:ESCAPE N?'~')",
parameter.ParameterName),
string.Format(#"contains([$1].[$2], #{0})",
parameter.ParameterName));
if (text == cmd.CommandText)
throw new Exception("FTS was not replaced on: " + text);
text = cmd.CommandText;
}
}
}
}
}
static class LanguageExtensions
{
public static bool In<T>(this T source, params T[] list)
{
return (list as IList<T>).Contains(source);
}
}
For example, if you have class Note with FTS-indexed field NoteText:
public class Note
{
public int NoteId { get; set; }
public string NoteText { get; set; }
}
and EF map for it
public class NoteMap : EntityTypeConfiguration<Note>
{
public NoteMap()
{
// Primary Key
HasKey(t => t.NoteId);
}
}
and context for it:
public class MyContext : DbContext
{
static MyContext()
{
DbInterception.Add(new FtsInterceptor());
}
public MyContext(string nameOrConnectionString) : base(nameOrConnectionString)
{
}
public DbSet<Note> Notes { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Configurations.Add(new NoteMap());
}
}
you can have quite simple syntax to FTS query:
class Program
{
static void Main(string[] args)
{
var s = FtsInterceptor.Fts("john");
using (var db = new MyContext("CONNSTRING"))
{
var q = db.Notes.Where(n => n.NoteText.Contains(s));
var result = q.Take(10).ToList();
}
}
}
That will generate SQL like
exec sp_executesql N'SELECT TOP (10)
[Extent1].[NoteId] AS [NoteId],
[Extent1].[NoteText] AS [NoteText]
FROM [NS].[NOTES] AS [Extent1]
WHERE contains([Extent1].[NoteText], #p__linq__0)',N'#p__linq__0 char(4096)',#p__linq__0='(john)
Please notice that you should use local variable and cannot move FTS wrapper inside expression like
var q = db.Notes.Where(n => n.NoteText.Contains(FtsInterceptor.Fts("john")));
I have found that the easiest way to implement this is to setup and configure full-text-search in SQL Server and then use a stored procedure. Pass your arguments to SQL, allow the DB to do its job and return either a complex object or map the results to an entity. You don't necessarily have to have dynamic SQL, but it may be optimal. For example, if you need paging, you could pass in PageNumber and PageSize on every request without the need for dynamic SQL. However, if the number of arguments fluctuates per query, it will be the optimal solution.
As the other guys mentioned, I would say start using Lucene.NET
Lucene has a pretty high learning curve, but I found an wrapper for it called "SimpleLucene", that can be found on CodePlex
Let me quote a couple of codeblocks from the blog to show you how easy it is to use. I've just started to use it, but got the hang of it really fast.
First, get some entities from your repository, or in your case, use Entity Framework
public class Repository
{
public IList<Product> Products {
get {
return new List<Product> {
new Product { Id = 1, Name = "Football" },
new Product { Id = 2, Name = "Coffee Cup"},
new Product { Id = 3, Name = "Nike Trainers"},
new Product { Id = 4, Name = "Apple iPod Nano"},
new Product { Id = 5, Name = "Asus eeePC"},
};
}
}
}
The next thing you want to do is create an index-definition
public class ProductIndexDefinition : IIndexDefinition<Product> {
public Document Convert(Product p) {
var document = new Document();
document.Add(new Field("id", p.Id.ToString(), Field.Store.YES, Field.Index.NOT_ANALYZED));
document.Add(new Field("name", p.Name, Field.Store.YES, Field.Index.ANALYZED));
return document;
}
public Term GetIndex(Product p) {
return new Term("id", p.Id.ToString());
}
}
and create an search index for it.
var writer = new DirectoryIndexWriter(
new DirectoryInfo(#"c:\index"), true);
var service = new IndexService();
service.IndexEntities(writer, Repository().Products, ProductIndexDefinition());
So, you now have an search-able index. The only remaining thing to do is.., searching! You can do pretty amazing things, but it can be as easy as this: (for greater examples see the blog or the documentation on codeplex)
var searcher = new DirectoryIndexSearcher(
new DirectoryInfo(#"c:\index"), true);
var query = new TermQuery(new Term("name", "Football"));
var searchService = new SearchService();
Func<Document, ProductSearchResult> converter = (doc) => {
return new ProductSearchResult {
Id = int.Parse(doc.GetValues("id")[0]),
Name = doc.GetValues("name")[0]
};
};
IList<Product> results = searchService.SearchIndex(searcher, query, converter);
The example here http://www.entityframework.info/Home/FullTextSearch is not complete solution. You will need to look into understand how the full text search works. Imagine you have a search field and the user types 2 words to hit search. The above code will throw an exception. You need to do pre-processing on the search phrase first to pass it to the query by using logical AND or OR.
for example your search phrase is "blah blah2" then you need to convert this into:
var searchTerm = #"\"blah\" AND/OR \"blah2\" ";
Complete solution would be:
value = Regex.Replace(value, #"\s+", " "); //replace multiplespaces
value = Regex.Replace(value, #"[^a-zA-Z0-9 -]", "").Trim();//remove non-alphanumeric characters and trim spaces
if (value.Any(Char.IsWhiteSpace))
{
value = PreProcessSearchKey(value);
}
public static string PreProcessSearchKey(string searchKey)
{
var splitedKeyWords = searchKey.Split(null); //split from whitespaces
// string[] addDoubleQuotes = new string[splitedKeyWords.Length];
for (int j = 0; j < splitedKeyWords.Length; j++)
{
splitedKeyWords[j] = $"\"{splitedKeyWords[j]}\"";
}
return string.Join(" AND ", splitedKeyWords);
}
this methods uses AND logic operator. You might pass that as an argument and use the method for both AND or OR operators.
You must escape none-alphanumeric characters otherwise it would throw exception when a user enters alpha numeric characters and you have no server site model level validation in place.
I recently had a similar requirement and ended up writing an IQueryable extension specifically for Microsoft full text index access, its available here IQueryableFreeTextExtensions
Is there any "automatic way" to casts an "Object" to a personalized Model Data Type in ActionScript 3?
Example:
package Example{
public class ExampleModel{
private _id:int;
private _randomAttribute:String;
public function ExampleModel(){
_id = 0;
_randomAttribute = "";
}
public function get id():int{
return _id;
}
public function set id(value:int):void{
_id = value;
}
public function get randomAttribute():String{
return _randomAttribute;
}
public function set randomAttribute(value:String):void{
_randomAttribute = value;
}
}
}
Then, in some part of my code, lets assume that I have something like this:
var _obj:Object = new Object();
_obj.id = 1;
obj.randomAttribute = "Hello World";
What I want would be something like:
var _exampleModel:ExampleModel = obj as ExampleModel;
But when I do this, the result on _exampleModel is null.
Any ideas?
Thanks.
EDIT:
According to Manish's answer, all I changed was the type of p var, which allows me to go through every kind of attribute:
public function fromObject(obj:Object):void{
//p:* includes every type of attributes.
for (var p:* in obj)
if (this.hasOwnProperty(p))
// Set private var directly.
this["_" + p] = obj[p];
}
Thanks Manish and rcdmk.
Manish's answer was enough for me and according to rcdmk's comment, the p:String isn't about the Type of data that the loop will go through, it is actually the name of the property, which makes sense because every name is a String.
The only way to automatically "cast" it is the following:
var model:Model = new Model();
var obj:Object = { id: "98123", name: "John Doe" };
for (var p:String in obj) {
if (model.hasOwnProperty(p))
model[p] = obj[p];
}
(Note: Model.id and Model.name are both type String in my example.)
A more proper way to do it, of course, is to pass the plain object to the Model object and let the Model object absorb it.
var model:Model = new Model(obj);
Or:
var model:Model = new Model();
model.fromObject(obj);
Where in the Model code you have:
public function Model(obj:Object = null)
{
if (obj != null)
fromObject(obj);
}
public function fromObject(obj:Object):void
{
for (var p:String in obj)
if (this.hasOwnProperty(p))
// Set private var directly.
this["_" + p] = obj[p];
}
This code can be in your abstract base Model class, and all your specific Model subclasses (e.g. ProductModel, CustomerModel, etc.) can use it automatically.
e.g.
public class ProductModel extends Model
{
public function ProductModel(obj:Object = null)
{
super(obj);
}
}
I'm building a rather large filter based on an SearchObject that has 50+ fields that can be searched.
Rather than building my where clause for each one of these individually I thought I'd use some slight of hand and try building custom attribute suppling the necessary information and then using reflection to build out each of my predicate statements (Using LinqKit btw). Trouble is, that the code finds the appropriate values in the reflection code and successfully builds a predicate for the property, but the "where" doesn't seem to actually generate and my query always returns 0 records.
The attribute is simple:
[AttributeUsage(AttributeTargets.Property, AllowMultiple=true)]
public class FilterAttribute: Attribute
{
public FilterType FilterType { get; set; } //enum{ Object, Database}
public string FilterPath { get; set; }
//var predicate = PredicateBuilder.False<Metadata>();
}
And this is my method that builds out the query:
public List<ETracker.Objects.Item> Search(Search SearchObject, int Page, int PageSize)
{
var predicate = PredicateBuilder.False<ETracker.Objects.Item>();
Type t = typeof(Search);
IEnumerable<PropertyInfo> pi = t.GetProperties();
string title = string.Empty;
foreach (var property in pi)
{
if (Attribute.IsDefined(property, typeof(FilterAttribute)))
{
var attrs = property.GetCustomAttributes(typeof(FilterAttribute),true);
var value = property.GetValue(SearchObject, null);
if (property.Name == "Title")
title = (string)value;
predicate.Or(a => GetPropertyVal(a, ((FilterAttribute)attrs[0]).FilterPath) == value);
}
}
var res = dataContext.GetAllItems().Take(1000)
.Where(a => SearchObject.Subcategories.Select(b => b.ID).ToArray().Contains(a.SubCategory.ID))
.Where(predicate);
return res.ToList();
}
The SearchObject is quite simple:
public class Search
{
public List<Item> Items { get; set; }
[Filter(FilterType = FilterType.Object, FilterPath = "Title")]
public string Title { get; set; }
...
}
Any suggestions will be greatly appreciated. I may well be going way the wrong direction and will take no offense if someone has a better alternative (or at least one that works)
You're not assigning your predicate anywhere. Change the line to this:
predicate = predicate.Or(a => GetPropertyVal(a, ((FilterAttribute)attrs[0]).FilterPath) == value);