Search Results

Search found 4866 results on 195 pages for 'bindable linq'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 17/195 | < Previous Page | 13 14 15 16 17 18 19 20 21 22 23 24  | Next Page >

  • Extending LINQ classes to my own partial classes in different namespaces?

    - by sah302
    I have a .dbml file which of course contains the auto-generated classes based on my tables. I would however, like to extend them to my own classes. Typically I design such that each of my tables get their own namespace in their own folder containing all of their associated dao and service classes. So if I am dealing with a page that only has to do with 'customers' for instance, I can only include the customerNS. But when using LINQ I seem to be unable to do this. I have tried removing a default namespace from the project, I have tried putting the .dbml file into it's own folder with a custom namespace and then adding a 'using' statement, but no nothing works. I also saw the Entity Namespace, Context Namespace, and Custom Tool Namespace properties associated with the .dbml file and tried setting all these to names x and trying 'using x' in my other class to allow me to extend partial classes, but it just doesn't work. Is this possible or do I have to keep all extended partial classes in the same namespace as the .dbml file?

    Read the article

  • How can I use linq to build an object from 1 row of data?

    - by Hcabnettek
    Hi All, I have a quick linq question. I have a stored proc that should return one row of data. I would like to use a lambda to build an object. Here's what I'm currently doing which works, but I know I should be able to use First instead of Select except I can't seem to get the syntax correct. Can anyone straighten me out here? Thanks for any help. var location = new GeoLocationDC(); DataSet ds = db.ExecuteDataSet(dbCommand); if(ds.Tables[0].Rows.Count == 1) { var rows = ds.Tables[0].AsEnumerable(); var x = rows.Select( c => new GeoLocationDC { Latitude = Convert.ToInt32(c.Field<string>("LATITUDE")), Longitude = Convert.ToInt32(c.Field<string>("LONGITUDE")) }).ToList(); if(x.Count > 0 ) { location = x[0]; } Cheers, ~ck }

    Read the article

  • LINQ to SQL for tables across databases. Or View?

    - by BritishDeveloper
    I have a Message table and a User table. Both are in separate databases. There is a userID in the Message table that is used to join to the User table to find things like userName. How can I create this in LINQ to SQL? I can't seem to do a cross database join. Should I create a View in the database and use that instead? Will that work? What will happen to CRUD against it? E.g. if I delete a message - surely it won't delete the user? I'd imagine it would throw an error. What to do? I can't move the tables into the same database!

    Read the article

  • Using Linq, how to separate a list in to grouped objects by name?

    - by Dr. Zim
    I have a table where a record looks like this varchar(255) Name varchar(255) Text varchar(255) Value Name is the DDL name, Text is what is displayed, and Value is returned upon selection. There are between one and twenty options for each Name. Without iterating though each option like a cursor, is there any way to pull out a list of objects, one for each unique DDL Name, using Linq and C#? A sample of the data: Beds '4 (10)' 4 Beds '5 (1)' 5 Beds '7 (1)' 7 Baths 'NA (13)' NULL Baths '0 (1)' 0 Baths '1 (13)' 1 I was thinking about doing an outer select to get the unique Names, then an inner select to get the list of options for it, then return the set as a List of a set of Lists.

    Read the article

  • Combine Hibernate class with @Bindable for SwingBuilder without Griffon?

    - by Misha Koshelev
    Dear All: I have implemented a back-end for my application in Groovy/Gradle, and am now trying to implement a GUI. I am using Hibernate for my data storage (with HSQLDB) per http://groovy.codehaus.org/Using+Hibernate+with+Groovy (with Jasypt for encryption) and it is working quite well. I was wondering if there are any good tips for using @Bindable with, e.g., an @Entity class such as @Entity class Book { @Id @GeneratedValue(strategy = GenerationType.AUTO) public Long id @OneToMany(cascade=CascadeType.ALL) public Set<Author> authors public String title String toString() { "$title by ${authors.name.join(', ')}" } } or if I am: (i) asking for Griffon (ii) completely on the wrong track? Thank you! Misha

    Read the article

  • How can I use external expressions in Linq with EF4 (and LINQKit)?

    - by neo
    I want to separate out often used expressions in linq queries. I'm using Entity Framework 4 and also LINQKit but I still don't know how I should do it the right way. Let me give you an example: Article article = dataContainer.Articles.FirstOrDefault(a => a.Id == id); IEnumerable<Comment> comments = (from c in container.Comments where CommentExpressions.IsApproved.Invoke(c) select c); public static class CommentExpressions { public static Expression<Func<Module, bool>> IsApproved { get { return m => m.IsApproved; } } } Of course the IsApproved expression would be something much more complicated. The problem is that the Invoke() won't work because I didn't call .asExpandable() from LINQKit on container.Comments but I can't call it because it's just an ICollection instead of an ObjectSet. So my question is: Do I always have to go through the data context when I want to include external expressions or can I somehow use it on the object I fetched (Article)? Any ideas or best practices? Thanks very much! neo

    Read the article

  • How to get rank from full-text search query with Linq to SQL?

    - by Stephen Jennings
    I am using Linq to SQL to call a stored procedure which runs a full-text search and returns the rank plus a few specific columns from the table Article. The rank column is the rank returned from the SQL function FREETEXTTABLE(). I've added this sproc to the data model designer with return type Article. This is working to get the columns I need; however, it discards the ranking of each search result. I'd like to get this information so I can display it to the user. So far, I've tried creating a new class RankedArticle which inherits from Article and adds the column Rank, then changing the return type of my sproc mapping to RankedArticle. When I try this, an InvalidOperationException gets thrown: Data member 'Int32 ArticleID' of type 'Heap.Models.Article' is not part of the mapping for type 'RankedArticle'. Is the member above the root of an inheritance hierarchy? I can't seem to find any other questions or Google results from people trying to get the rank column, so I'm probably missing something obvious here.

    Read the article

  • ASP.NET MVC 2: How to write this Linq SQL as a Dynamic Query (using strings)?

    - by Dr. Zim
    Skip to the "specific question" as needed. Some background: The scenario: I have a set of products with a "drill down" filter (Query Object) populated with DDLs. Each progressive DDL selection will further limit the product list as well as what options are left for the DDLs. For example, selecting a hammer out of tools limits the Product Sizes to only show hammer sizes. Current setup: I created a query object, sent it to a repository, and fed each option to a SQL "table valued function" where null values represent "get all products". I consider this a good effort, but far from DDD acceptable. I want to avoid any "programming" in SQL, hopefully doing everything with a repository. Comments on this topic would be appreciated. Specific question: How would I rewrite this query as a Dynamic Query? A link to something like 101 Linq Examples would be fantastic, but with a Dynamic Query scope. I really want to pass to this method the field in quotes "" for which I want a list of options and how many products have that option. (from p in db.Products group p by p.ProductSize into g select new Category { PropertyType = g.Key, Count = g.Count() }).Distinct(); Each DDL option will have "The selection (21)" where the (21) is the quantity of products that have that attribute. Upon selecting an option, all other remaining DDLs will update with the remaining options and counts.

    Read the article

  • Can I use the auto-generated Linq-to-SQL entity classes in 'disconnected' mode?

    - by Gary McGill
    Suppose I have an automatically-generated Employee class based on the Employees table in my database. Now suppose that I want to pass employee data to a ShowAges method that will print out name & age for a list of employees. I'll retrieve the data for a given set of employees via a linq query, which will return me a set of Employee instances. I can then pass the Employee instances to the ShowAges method, which can access the Name & Age fields to get the data it needs. However, because my Employees table has relationships with various other tables in my database, my Employee class also has a Department field, a Manager field, etc. that provide access to related records in those other tables. If the ShowAges method were to invoke any of those methods, this would cause lots more data to be fetched from the database, on-demand. I want to be sure that the ShowAges method only uses the data I have already fetched for it, but I really don't want to have to go to the trouble of defining a new class which replicates the Employee class but has fewer methods. (In my real-world scenario, the class would have to be considerably more complex than the Employee class described here; it would have several 'joined' classes that do need to be populated, and others that don't). Is there a way to 'switch off' or 'disconnect' the Employees instances so that an attempt to access any property or related object that's not already populated will raise an exception? If not, then I assume that since this must be a common requirement, there might be an already-established pattern for doing this sort of thing?

    Read the article

  • Can LINQ expression classes implement the observer pattern instead of deferred execution?

    - by Tormod
    Hi. We have issues within an application using a state machine. The application is implemented as a windows service and is iteration based (it "foreaches" itself through everything) and there are myriads of instances being processed by the state machine. As I'm reading the MEAP version of Jon Skeets book "C# in Depth, 2nd ed", I'm wondering if I can change the whole thing to use linq expression instances so that guards and conditions are represented using expression trees. We are building many applications on this state machine engine and would probably greatly benefit from the new Expression tree visualizer in VS 2010 Now, simple example. If I have an expression tree where there is an OR Expression condition with two sub nodes, is there any way that these can implement the observer pattern so that the expression tree becomes event driven? If a condition change, it should notify its parent node (the OR node). Since the OR node then changes from "false" to "true", then it should notify ITS parent and so on. I love the declarative model of expression trees, but the deferred execution model works in opposite direction of the control flow if you want event based "live" conditions. Am I off on a wild goose chase here? Or is there some concept in the BCL that may help me achieve this?

    Read the article

  • LINQ to SQL - How to efficiently do either an AND or an OR search for multiple criteria

    - by Dan Diplo
    I have an ASP.NET MVC site (which uses Linq To Sql for the ORM) and a situation where a client wants a search facility against a bespoke database whereby they can choose to either do an 'AND' search (all criteria match) or an 'OR' search (any criteria match). The query is quite complex and long and I want to know if there is a simple way I can make it do both without having to have create and maintain two different versions of the query. For instance, the current 'AND' search looks something like this (but this is a much simplified version): private IQueryable<SampleListDto> GetSampleSearchQuery(SamplesCriteria criteria) { var results = from r in Table where (r.Id == criteria.SampleId) && (r.Status.SampleStatusId == criteria.SampleStatusId) && (r.Job.JobNumber.StartsWith(criteria.JobNumber)) && (r.Description.Contains(criteria.Description)) select r; } I could copy this and replace the && with || operators to get the 'OR' version, but feel there must be a better way of achieving this. Does anybody have any suggestions how this can be achieved in an efficient and flexible way that is easy to maintain? Thanks.

    Read the article

  • [C#]How to introduce retry logic into LINQ to SQL to deal with timeouts?

    - by codemonkie
    I need to find ways to add retry mechanism to my DB calls in case of timeouts, LINQ to SQL is used to call some sprocs in my code... using (MyDataContext dc = new MyDataContext()) { int result = -1; //denote failure int count = 0; while ((result < 0) && (count < MAX_RETRIES)) { result = dc.myStoredProc1(...); count++; } result = -1; count = 0; while ((result < 0) && (count < MAX_RETRIES)) { result = dc.myStoredProc2(...); count++; } ... ... } Not sure if the code above is right or posed any complications. It'll be nice to throw an exception after MAX_RETRIES has reached, but I dunno how and where to throw them appropriately :-) Any helps appreciated.

    Read the article

  • Important question about linq to SQL performance on high loaded web applications

    - by Alex
    I started working with linq to SQL several weeks ago. I got really tired of working with SQL server directly through the SQL queries (sqldatareader, sqlcommand and all this good stuff).  After hearing about linq to SQL and mvc I quickly moved all my projects to these technologies. I expected linq to SQL work slower but it suprisongly turned out to be pretty fast, primarily because I always forgot to close my connections when using datareaders. Now I don't have to worry about it. But there's one problem that really bothers me. There's one page that's requested thousands of times a day. The system gets data in the beginning, works with it and updates it. Primarily the updates are ++ @ -- (increase and decrease values). I used to do it like this UPDATE table SET value=value+1 WHERE ID=@I'd It worked with no problems obviously. But with linq to SQL the data is taken in the beginning, moved to the class, changed and then saved. Stats.registeredusers++; Db.submitchanges(); Let's say there were 100 000 users. Linq will say "let it be 100 001" instead of "let it be increased by 1". But if there value of users has already been increased (that happens in my site all the time) then linq will be like oops, this value is already 100 001. Whatever I'll throw an exception" You can change this behavior so that it won't throw an exception but it still will not set the value to 100 002. Like I said, it happened with me all the time. The stas value was increased twice a second on average. I simply had to rewrite this chunk of code with classic ado net. So my question is how can you solve the problem with linq

    Read the article

  • LINQ Query using UDF that receives parameters from the query

    - by Ben Fidge
    I need help using a UDF in a LINQ which calculates a users position from a fixed point. int pointX = 567, int pointY = 534; // random points on a square grid var q = from n in _context.Users join m in _context.GetUserDistance(n.posY, n.posY, pointX, pointY, n.UserId) on n.UserId equals m.UserId select new User() { PosX = n.PosX, PosY = n.PosY, Distance = m.Distance, Name = n.Name, UserId = n.UserId }; The GetUserDistance is just a UDF that returns a single row in a TVP with that users distance from the points deisgnated in pointX and pointY variables, and the designer generates the following for it: [global::System.Data.Linq.Mapping.FunctionAttribute(Name="dbo.GetUserDistance", IsComposable=true)] public IQueryable<GetUserDistanceResult> GetUserDistance([global::System.Data.Linq.Mapping.ParameterAttribute(Name="X1", DbType="Int")] System.Nullable<int> x1, [global::System.Data.Linq.Mapping.ParameterAttribute(Name="X2", DbType="Int")] System.Nullable<int> x2, [global::System.Data.Linq.Mapping.ParameterAttribute(Name="Y1", DbType="Int")] System.Nullable<int> y1, [global::System.Data.Linq.Mapping.ParameterAttribute(Name="Y2", DbType="Int")] System.Nullable<int> y2, [global::System.Data.Linq.Mapping.ParameterAttribute(Name="UserId", DbType="Int")] System.Nullable<int> userId) { return this.CreateMethodCallQuery<GetUserDistanceResult>(this, ((MethodInfo)(MethodInfo.GetCurrentMethod())), x1, x2, y1, y2, userId); } when i try to compile i get The name 'n' does not exist in the current context

    Read the article

  • linq: SQL performance on high loaded web applications

    - by Alex
    I started working with linq to SQL several weeks ago. I got really tired of working with SQL server directly through the SQL queries (sqldatareader, sqlcommand and all this good stuff).  After hearing about linq to SQL and mvc I quickly moved all my projects to these technologies. I expected linq to SQL work slower but it suprisongly turned out to be pretty fast, primarily because I always forgot to close my connections when using datareaders. Now I don't have to worry about it. But there's one problem that really bothers me. There's one page that's requested thousands of times a day. The system gets data in the beginning, works with it and updates it. Primarily the updates are ++ @ -- (increase and decrease values). I used to do it like this UPDATE table SET value=value+1 WHERE ID=@I'd It worked with no problems obviously. But with linq to SQL the data is taken in the beginning, moved to the class, changed and then saved. Stats.registeredusers++; Db.submitchanges(); Let's say there were 100 000 users. Linq will say "let it be 100 001" instead of "let it be increased by 1". But if there value of users has already been increased (that happens in my site all the time) then linq will be like oops, this value is already 100 001. Whatever I'll throw an exception" You can change this behavior so that it won't throw an exception but it still will not set the value to 100 002. Like I said, it happened with me all the time. The stas value was increased twice a second on average. I simply had to rewrite this chunk of code with classic ado net. So my question is how can you solve the problem with linq

    Read the article

  • How to write this Linq SQL as a Dynamic Query (using strings)?

    - by Dr. Zim
    Skip to the "specific question" as needed. Some background: The scenario: I have a set of products with a "drill down" filter (Query Object) populated with DDLs. Each progressive DDL selection will further limit the product list as well as what options are left for the DDLs. For example, selecting a hammer out of tools limits the Product Sizes to only show hammer sizes. Current setup: I created a query object, sent it to a repository, and fed each option to a SQL "table valued function" where null values represent "get all products". I consider this a good effort, but far from DDD acceptable. I want to avoid any "programming" in SQL, hopefully doing everything with a repository. Comments on this topic would be appreciated. Specific question: How would I rewrite this query as a Dynamic Query? A link to something like 101 Linq Examples would be fantastic, but with a Dynamic Query scope. I really want to pass to this method the field in quotes "" for which I want a list of options and how many products have that option. from p in db.Products group p by p.ProductSize into g select new Category { PropertyType = g.Key, Count = g.Count() } Each DDL option will have "The selection (21)" where the (21) is the quantity of products that have that attribute. Upon selecting an option, all other remaining DDLs will update with the remaining options and counts. Edit: Additional notes: .OrderBy("it.City") // "it" refers to the entire record .GroupBy("City", "new(City)") // This produces a unique list of City .Select("it.Count()") //This gives a list of counts... getting closer .Select("key") // Selects a list of unique City .Select("new (key, count() as string)") // +1 to me LOL. key is a row of group .GroupBy("new (City, Manufacturer)", "City") // New = list of fields to group by .GroupBy("City", "new (Manufacturer, Size)") // Second parameter is a projection Product .Where("ProductType == @0", "Maps") .GroupBy("new(City)", "new ( null as string)")// Projection not available later? .Select("new (key.City, it.count() as string)")// GroupBy new makes key an object Product .Where("ProductType == @0", "Maps") .GroupBy("new(City)", "new ( null as string)")// Projection not available later? .Select("new (key.City, it as object)")// the it object is the result of GroupBy var a = Product .Where("ProductType == @0", "Maps") .GroupBy("@0", "it", "City") // This fails to group Product at all .Select("new ( Key, it as Product )"); // "it" is property cast though What I have learned so far is LinqPad is fantastic, but still looking for an answer. Eventually, completely random research like this will prevail I guess. LOL. Edit:

    Read the article

  • Linq Left Outer Join

    - by Neil
    I am new to LINQ and am trying to convert a SQL query to LINQ: SQL: left outer join PRODUCT_BEST_USE pbu on pbu.PRODUCT_GUID = @uProductId and pbu.BEST_USE_GUID = bu.BEST_USE_GUID LINQ: from PBU in PRODUCT_BEST_USE.Where(PBU=>PBU.PRODUCT_GUID == p.PRODUCT_GUID).DefaultIfEmpty() When I add and PBU.BEST_USE_GUID equals BU.BEST_USE_GUID, I get an error: "A query body must end with a select clause or a group clause" Here is the full Linq query: from p in PRODUCT join BU in BEST_USE on p.CATEGORY_GUID equals BU.CATEGORY_GUID from PBU in PRODUCT_BEST_USE.Where(PBU=>PBU.PRODUCT_GUID == p.PRODUCT_GUID).DefaultIfEmpty() and PBU.BEST_USE_GUID equals BU.BEST_USE_GUID where p.PRODUCT_GUID == new Guid("d317752b-581d-4f43-92fa-4a4af91009f5") select new { BU.NAME, PBU.PRODUCT_BEST_USE_GUID }

    Read the article

  • Linq To Sql or classic ADO.net?

    - by Spyros
    I am asking my self many times before start writting a new app or data access library , should I use LinqToSql or classic ADO.net , I have used both and the development time I spend on building an app with Linq To sql is like the 1/3 compared to ADO.net. The only think I like using Linq to sql is that I dont have to design the domain objects Linq does that for me and saves me from spend my time on boring things :P But is Linq to sql suitable for large scale projects , is there an overhead that we can avoid when using ADO.net ?

    Read the article

  • Future of Linq to Sql and Entity Framework

    - by ENES TAYLAN
    I work on a project and want to use an ORM. What should I use: Linq to Sql or Entity Framework? Linq to Sql provides more opportunities, as I see, for example support for enumeration types. However, also it is said that, Linq to Sql was for playing and learning for Linq and future strategy of Microsoft lies on Entity Framework. So which one should I use?

    Read the article

  • Linq To Text Files

    - by j-t-s
    Hi All I have a Text File (Sorry, I'm not allowed to work on XML files :(), and it includes customer records. Each text file looks like: Account_ID: 98734BLAH9873 User Name: something_85 First Name: ILove Last Name: XML Age: 209 etc... And I need to be able to use LINQ to get the data from these text files and just store them in memory. I have seen many Linq to SQL, Linq to BLAH but nothing for Linq to Text. Can someone please help me out abit? Thank you

    Read the article

  • How to write Asynchronous LINQ query?

    - by Morgan Cheng
    After I read a bunch of LINQ related stuff, I suddenly realized that no articles introduce how to write asynchronous LINQ query. Suppose we use LINQ to SQL, below statement is clear. However, if the SQL database responds slowly, then the thread using this block of code would be hindered. var result = from item in Products where item.Price > 3 select item.Name; foreach (var name in result) { Console.WriteLine(name); } Seems that current LINQ query spec doesn't provide support to this. Is there any way to do asynchronous programming LINQ? It works like there is a callback notification when results are ready to use without any blocking delay on I/O.

    Read the article

  • Linq-to-sql Compiled Query returns object NOT belonging to submitted DataContext ?

    - by Vladimir Kojic
    Compiled query: public static class Machines { public static readonly Func<OperationalDataContext, short, Machine> QueryMachineById = CompiledQuery.Compile((OperationalDataContext db, short machineID) => db.Machines.Where(m => m.MachineID == machineID).SingleOrDefault() ); public static Machine GetMachineById(IUnitOfWork unitOfWork, short id) { Machine machine; // Old code (working) //var machineRepository = unitOfWork.GetRepository<Machine>(); //machine = machineRepository.Find(m => m.MachineID == id).SingleOrDefault(); // New code (making problems) machine = QueryMachineById(unitOfWork.DataContext, id); return machine; } It looks like compiled query is returning result from another data context [TestMethod] public void GetMachinesTest() { using (var unitOfWork = IoC.Get<IUnitOfWork>()) { // Compile Query var machine = Machines.GetMachineById(unitOfWork, 3); } using (var unitOfWork = IoC.Get<IUnitOfWork>()) { var machineRepository = unitOfWork.GetRepository<Machine>(); // Get From Repository var machineFromRepository = machineRepository.Find(m => m.MachineID == 2).SingleOrDefault(); var machine = Machines.GetMachineById(unitOfWork, 2); VerifyHuskyHostMachine(machineFromRepository, 2, "Machine 2", "222222", "H400RS", "MachineIconB.xaml", false, true, LicenseType.Licensed, InterfaceType.HuskyHostV2, "10.0.97.2:8080", "10.0.97.2", 8080, "4.0"); VerifyHuskyHostMachine(machine, 2, "Machine 2", "222222", "H400RS", "MachineIconB.xaml", false, true, LicenseType.Licensed, InterfaceType.HuskyHostV2, "10.0.97.2:8080", "10.0.97.2", 8080, "4.0"); Assert.AreSame(machineFromRepository, machine); // FAIL } } If I run other (complex) unit tests I'm getting as expected: An attempt has been made to Attach or Add an entity that is not new, perhaps having been loaded from another DataContext. Another Important information is that this test is under TransactionScope! UPDATE: It looks like next link is describing similar problem (is this bug solved ?): http://social.msdn.microsoft.com/Forums/en-US/linqprojectgeneral/thread/9bcffc2d-794e-4c4a-9e3e-cdc89dad0e38

    Read the article

  • What join in Linq i have to use to do what i want?

    - by Garcia Julien
    Hi, I have two dataset from different server. I have result like that (if image doesn't work my data) The problem is at last, i've got only the result from the first table like that And i would like to have all the result for different job type like that asset job jan feb mar ... 5000 acc 10 11 12 5000 over 10 11 12 The problem is not solve with a right join because it's the same problem Could you help me? Thank Ju

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 13 14 15 16 17 18 19 20 21 22 23 24  | Next Page >