Search Results

Search found 19804 results on 793 pages for 'linq to xml'.

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 178/793 | < Previous Page | 174 175 176 177 178 179 180 181 182 183 184 185  | Next Page >

  • LINQ TO SQL error: An attempt has been made to Attach or Add an entity that is not new...

    - by Collin Estes
    "An attempt has been made to Attach or Add an entity that is not new, perhaps having been loaded from another DataContext. This is not supported." I have scene a lot of solutions dealing with the Attach() method but I'm just trying to add in a new record. Not sure what is going on. Here is my code, It is failing on the star'd line.: try { LINQDataContext datacontext = new LINQDataContext(); TrackableItem ti = datacontext.TrackableItems.FirstOrDefault(_t => _t.pkId == obj.fkTrackableItemId); arcTrackableItem ati = new arcTrackableItem(); ati.barcode = ti.barcode; ati.dashNumber = ti.dashNumber; ati.dateDown = ti.dateDown; ati.dateUp = ti.dateUp; ati.fkItemStatusId = ti.fkItemStatusId; ati.fkItemTypeId = ti.fkItemTypeId; ati.partNumber = ti.partNumber; ati.serialNumber = ti.serialNumber; ati.archiveDate = DateTime.Now; datacontext.arcTrackableItems.InsertOnSubmit(ati); datacontext.SubmitChanges(); arcPWR aItem = new arcPWR(); aItem.comments = obj.comments; aItem.fkTrackableItemId = ati.pkId; aItem.fkPWRStatusId = obj.fkPWRStatusId; aItem.PwrStatus = obj.PwrStatus; **datacontext.arcPWRs.InsertOnSubmit(aItem);** datacontext.SubmitChanges();

    Read the article

  • LINQ: why does this query not work on an ArrayList?

    - by Benny
    public static ArrayList GetStudentAsArrayList() { ArrayList students = new ArrayList { new Student() { RollNumber = 1,Name ="Alex " , Section = 1 ,HostelNumber=1 }, new Student() { RollNumber = 2,Name ="Jonty " , Section = 2 ,HostelNumber=2 } }; return students; } The following code doesn't compile. The error is ArrayList is not IEnumerable ArrayList lstStudents = GetStudentAsArrayList(); var res = from r in lstStudents select r; This compiles: ArrayList lstStudents = GetStudentAsArrayList(); var res = from Student r in lstStudents select r; Can anybody explain what the difference is between these two snippets? Why the second works?

    Read the article

  • How do I add ROW_NUMBER to a LINQ query or Entity?

    - by Whozumommy
    I'm stumped by this easy data problem. I'm using the Entity framework and have a database of products. My results page returns a paginated list of these products. Right now my results are ordered by the number of sales of each product, so my code looks like this: return Products.OrderByDescending(u => u.Sales.Count()); This returns an IQueryable dataset of my entities, sorted by the number of sales. I want my results page to show the rank of each product (in the dataset). My results should look like this: Page #1 1. Bananas 2. Apples 3. Coffee Page #2 4. Cookies 5. Ice Cream 6. Lettuce I'm expecting that I just want to add a column in my results using the SQL ROW_NUMBER variable...but I don't know how to add this column to my results datatable. My resulting page does contain a foreach loop, but since I'm using a paginated set I'm guessing using that number to fake a ranking number would NOT be the best approach. So my question is, how do I add a ROW_NUMBER column to my query results in this case?

    Read the article

  • Is this Where condition in Linq-to-sql join correct?

    - by Pandiya Chendur
    I have the following Iqueryable method to show details of a singl material, public IQueryable<Materials> GetMaterial(int id) { return from m in db.Materials join Mt in db.MeasurementTypes on m.MeasurementTypeId equals Mt.Id where m.Mat_id equals id select new Materials() { Id = Convert.ToInt64(m.Mat_id), Mat_Name = m.Mat_Name, Mes_Name = Mt.Name, }; } Any suggestion....

    Read the article

  • What's a clean way to break up a DataTable into chunks of a fixed size with Linq?

    - by Michael Haren
    Update: Here's a similar question Suppose I have a DataTable with a few thousand DataRows in it. I'd like to break up the table into chunks of smaller rows for processing. I thought C#3's improved ability to work with data might help. This is the skeleton I have so far: DataTable Table = GetTonsOfData(); // Chunks should be any IEnumerable<Chunk> type var Chunks = ChunkifyTableIntoSmallerChunksSomehow; // ** help here! ** foreach(var Chunk in Chunks) { // Chunk should be any IEnumerable<DataRow> type ProcessChunk(Chunk); } Any suggestions on what should replace ChunkifyTableIntoSmallerChunksSomehow? I'm really interested in how someone would do this with access C#3 tools. If attempting to apply these tools is inappropriate, please explain! Update 3 (revised chunking as I really want tables, not ienumerables; going with an extension method--thanks Jacob): Final implementation: Extension method to handle the chunking: public static class HarenExtensions { public static IEnumerable<DataTable> Chunkify(this DataTable table, int chunkSize) { for (int i = 0; i < table.Rows.Count; i += chunkSize) { DataTable Chunk = table.Clone(); foreach (DataRow Row in table.Select().Skip(i).Take(chunkSize)) { Chunk.ImportRow(Row); } yield return Chunk; } } } Example consumer of that extension method, with sample output from an ad hoc test: class Program { static void Main(string[] args) { DataTable Table = GetTonsOfData(); foreach (DataTable Chunk in Table.Chunkify(100)) { Console.WriteLine("{0} - {1}", Chunk.Rows[0][0], Chunk.Rows[Chunk.Rows.Count - 1][0]); } Console.ReadLine(); } static DataTable GetTonsOfData() { DataTable Table = new DataTable(); Table.Columns.Add(new DataColumn()); for (int i = 0; i < 1000; i++) { DataRow Row = Table.NewRow(); Row[0] = i; Table.Rows.Add(Row); } return Table; } }

    Read the article

  • How do I get a linq to sql group by query into the asp.net mvc view?

    - by Brad Wetli
    Sorry for the newbie question, but I have the following query that groups parking spaces by their garage, but I can't figure out how to iterate the data in the view. I guess I should strongly type the view but am a newbie and having lots of problems figuring this out. Any help would be appreciated. Public Function FindAllSpaces() Implements ISpaceRepository.FindAllSpaces Dim query = _ From s In db.spaces _ Order By s.name Ascending _ Group By s.garageid Into spaces = Group _ Order By garageid Ascending Return query End Function The controller is taking the query object as is and putting it into the viewdata.model and as stated the view is not currently strongly typed as I haven't been able to figure out how to do this. I have run the query successfully in linqpad.

    Read the article

  • Locked DataGridView. Linq is a problem ?

    - by phenevo
    Hi, I get the collection from webservice: var allPlaceHolders = (from ph in new MyService().GetPlaceHolders() select ph).Select(l => new { Code = l.Code, Name = l.Name, Related = false }).ToList(); dgPlaceHoldersAdd.DataSource = allPlaceHolders; Designer.cs: this.dgPlaceHoldersAdd.ColumnHeadersHeightSizeMode = System.Windows.Forms.DataGridViewColumnHeadersHeightSizeMode.AutoSize; this.dgPlaceHoldersAdd.Location = new System.Drawing.Point(3, 54); this.dgPlaceHoldersAdd.Name = "dgPlaceHoldersAdd"; this.dgPlaceHoldersAdd.RowHeadersVisible = false; this.dgPlaceHoldersAdd.Size = new System.Drawing.Size(286, 151); this.dgPlaceHoldersAdd.TabIndex = 15; The problem is, that I can't changing value of checkBox column. I has enabled AutoGeneratedColumns (In datagridview at start there is not any column)

    Read the article

  • What is the best way to return result from business layer to presentation layer when using linq - I

    - by samsur
    I have a business layer that has DTOs that are used in the presentation layer. This application uses entity framework. Here is an example of a class called RoleDTO public class RoleDTO { public Guid RoleId { get; set; } public string RoleName { get; set; } public string RoleDescription { get; set; } public int? OrganizationId { get; set; } } In the BLL I want to have a method that returns a list of DTO.. I would like to know which is the better approach: returning IQueryable or list of DTOs. Although i feel that returning Iqueryable is not a good idea because the connection needs to be open. Here are the 2 different methods using the different approaches public class RoleBLL { private servicedeskEntities sde; public RoleBLL() { sde = new servicedeskEntities(); } public IQueryable<RoleDTO> GetAllRoles() { IQueryable<RoleDTO> role = from r in sde.Roles select new RoleDTO() { RoleId = r.RoleID, RoleName = r.RoleName, RoleDescription = r.RoleDescription, OrganizationId = r.OrganizationId }; return role; } Note: in the above method the datacontext is a private attribute and set in the constructor, so that the connection stays opened. Second approach public static List GetAllRoles() { List roleDTO = new List(); using (servicedeskEntities sde = new servicedeskEntities()) { var roles = from pri in sde.Roles select new { pri.RoleID, pri.RoleName, pri.RoleDescription }; //Add the role entites to the DTO list and return. This is necessary as anonymous types can be returned acrosss methods foreach (var item in roles) { RoleDTO roleItem = new RoleDTO(); roleItem.RoleId = item.RoleID; roleItem.RoleDescription = item.RoleDescription; roleItem.RoleName = item.RoleName; roleDTO.Add(roleItem); } return roleDTO; } Please let me know, if there is a better approach - Thanks,

    Read the article

  • Is it possible to coerce string values in xml to bool?

    - by Kugel
    Let's suppose I have xml like this one: <Server Active="No"> <Url>http://some.url</Url> </Server> C# class looks like this: public class Server { [XmlAttribute()] public string Active { get; set; } public string Url { get; set; } } Is it possible to change Active property to type bool and have XmlSerializer coerce "Yes" "No" to bool values? Edit: Xml is received, I cannot change it. So, in fact, i'm interested in deserialization only.

    Read the article

  • How can I use linq to initialize an array of repeated elements?

    - by Eric
    At present, I'm using something like this to build a list of 10 objects: myList = (from _ in Enumerable.Range(0, 9) select new MyObject {...}).toList() This is based off my python background, where I'd write: myList = [MyObject(...) for _ in range(10)] Note that I want my list to contain 10 instances of my object, not the same instance 10 times. Is this still a sensible way to do things in C#? Is there a cost to doing it this way over a simple for loop?

    Read the article

  • linq-to-sql "an attempt has been made to attach or add an entity that is not new"?

    - by Curtis White
    I've been getting several errors: cannot add an entity with a key that is already in use An attempt has been made to attach or add an entity that is not new, perhaps having been loaded from another datacontext In case 1, this stems from trying to set the key for an entity versus the entity. In case 2, I'm not attaching an entity but I am doing this: MyParent.Child = EntityFromOtherDataContext; I've been using using the pattern of wrap everything with a using datacontext. In my case, I am using this in a web forms scenario, and obviously moving the datacontext object to a class wide member variables solves this. My questions are thus 2 fold: How can I get rid of these errors and not have to structure my program in an odd way or pass the datacontext around while keeping the local-wrap pattern? I assume I could make another hit to the database but that seems very inefficient. Would most people recommend that moving the datacontext to the class wide scope is desirable for web pages?

    Read the article

  • How do you compare dates in a LINQ query?

    - by Gina
    I am tring to compare a date from a asp calendar control to a date in the table.... here's what i have... it doesn't like the == ? var query = from details in db.TD_TravelCalendar_Details where details.StartDate == calStartDate.SelectedDate && details.EndDate == calEndDate.SelectedDate select details;

    Read the article

  • Trying to parse xml, but xmldocument.loadxml() is trying to download?

    - by maxp
    I have a string input that i do not know whether or not is valid xml. I think the simplest aprroach is to wrap new XmlDocument().LoadXml(strINPUT); In a try/catch. The problem im facing is, sometimes strINPUT is an html file, if the header of this file contains <!DOCTYPE html PUBLIC ""-//W3C//DTD XHTML 1.0 Transitional//EN"" ""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd""> <html xml:lang=""en-GB"" xmlns=""http://www.w3.org/1999/xhtml"" lang=""en-GB""> ...like many do, it actually tries to make a connection to the w3.org url, which i really dont want it doing. Anyone know if its possible to just parse the string without trying to be clever and checking external urls? Failing that is there an alternative to xmldocument?

    Read the article

  • An attempt has been made to Attach or Add an entity that is not new Linq to Sql error

    - by Collin Oconnor
    I have a save function for my order entity that looks like this and it breaks on the sumbmitChanges line: public void SaveOrder ( Order order ) { if (order.OrderId == 0) orderTable.InsertOnSubmit(order); else if (orderTable.GetOriginalEntityState(order) == null) { orderTable.Attach(order); orderTable.Context.Refresh(RefreshMode.KeepCurrentValues , order); } orderTable.Context.SubmitChanges(); } The order entity contains two other entities; an Address entity and a credit card entity. Now i want these two entities to be null sometimes. Now my guess for why this is throwing an error is because that both of these entites that are inside order are null. If this is the case, How can I insert an new order into the database with both entities (Address and creditCard) being null.

    Read the article

  • Differences between query using LINQ and IQueryable interface directly?

    - by JohnMetta
    Using Entity Framework 4, and given: ObjectSet<Thing> AllThings = Context.CreateObjectSet<Thing>; public IQueryable<Thing> ByNameA(String name) { IQueryable<Thing> query = from o in AllThings where o.Name == name select o; return query; } public IQueryable<Thing> ByNameB(String name) { return AllThings.Where((o) => o.Name == name); } Both return IQueryable< instances, and thus the query doesn't hit the server until something like ToList() is called, right? Is it purely readability that is the difference, or are the using fundamentally different technologies on the back-end?

    Read the article

  • How to get some xml that comes before and a little from after a DOM Node.

    - by startoftext
    I am using java and I am pretty open to using w3c DOM or DOM4J at this point. So lets say I have a Node like a text node that I have found something interesting in, like say an occurrence of a substring in the nodes text. If I want to get a string with a number characters preceding that node and a few characters after that node how may I do that? Basically I need to be able to display a snippet of the original xml around the occurrence of that string. The problem I have with getting the parent node for example and then calling asXML is that I no longer know the exact location of the substring in the text node. If I search again for that string value in the parents xml then I may find 2 occurrences or many more if the parent has other children that contain an occurrence of that string. Much appreciation if any one can answer this question.

    Read the article

  • How to use pom.xml/Maven to initialize a local thoughtsite (App Engine sample) project in Eclipse?

    - by ovr
    This sample app ("thoughtsite") for App Engine contains a pom.xml in its trunk: http://code.google.com/p/thoughtsite/source/browse/#svn/trunk But I don't know what command to run in Maven to set up the project locally. (The README doesn't mention anything about Maven.) I tried to just import the project code directly into Eclipse but it doesn't look like it's in an appropriate format for a direct import. So I assume I need to do something with Maven to get it set up correctly. I haven't really used Maven before so I'm not sure what command I would need to run to set everything up. The pom.xml seems like it downloads a bunch of dependencies for the project like the Spring jar files which I don't see anywhere else in the svn repository.

    Read the article

  • Why does LINQ-to-Entites recognize my custom method?

    - by BlueRaja The Green Unicorn
    This works: (from o in Entities.WorkOrderSet select o) .Where(MyCustomMethod); This does not: (from o in Entities.WorkOrderSet select new { WorkOrder = o }) .Where(o => MyCustomMethod(o.WorkOrder); I understand why the second doesn't work - but why in the world does the first work!? Shouldn't I get a "custom method not recognized?" For reference, here is MyCustomMethod public bool MyCustomMethod(WorkOrder workOrder) { return !workOrder.WorkOrderNum.StartsWith("A", StringComparison.CurrentCultureIgnoreCase); }

    Read the article

  • Expand in linq not loading inner data collections from service.

    - by Kit
    I am seeing odd behavior with service queries! I am using MVVM pattern for a silverlight 3 app on 3.5 framework and Dataservices 1.5. The following code eager loads correctly the parent object and the child heirarchy perfectly IF and ONLY IF I am preloading the data. But I would like to fetch a different set of the parent object (and its child heirarchy) on different button clicks. What I am seeing is that on button click, only the parent object is retrieved, and the child heirarchy contains nothing. Any suggestions? Any ideas how to tackle this? Thanks all. The method: DataServiceQuery serviceQuery = (DataServiceQuery)(from m1 in dbEntities.gis_Region.Expand("gis_RegionValue/gis_Measure") where m1.RegionGuid == new Guid(regionGuid) select m1); serviceQuery.BeginExecute(GetRegionDetailAsyncResult, serviceQuery); The wired Async Result: DataServiceQuery query = (DataServiceQuery)result.AsyncState; gis_Region region = query.EndExecute(result).First();

    Read the article

  • Why do LINQ to Entities does not recognize certain Methods?

    - by Luiscencio
    Why cant I do this: usuariosEntities usersDB = new usuariosEntities(); foreach (DataGridViewRow user in dgvUsuarios.Rows) { var rowtoupdate = usersDB.usuarios.Where( u => u.codigo_usuario == Convert.ToInt32(user.Cells[0].Value) ).First(); rowtoupdate.password = user.Cells[3].Value.ToString(); } usersDB.SaveChanges(); And have to do this: usuariosEntities usersDB = new usuariosEntities(); foreach (DataGridViewRow user in dgvUsuarios.Rows) { int usercode = Convert.ToInt32(user.Cells[0].Value); var rowtoupdate = usersDB.usuarios.Where(u => u.codigo_usuario == usercode).First(); rowtoupdate.password = user.Cells[3].Value.ToString(); } usersDB.SaveChanges(); I must admint it is a more readable code but why cant this be done?

    Read the article

  • How can I implement NotOfType<T> in LINQ that has a nice calling syntax?

    - by Lette
    I'm trying to come up with an implementation for NotOfType, which has a readable call syntax. NotOfType should be the complement to OfType<T> and would consequently yield all elements that are not of type T My goal was to implement a method which would be called just like OfType<T>, like in the last line of this snippet: public abstract class Animal {} public class Monkey : Animal {} public class Giraffe : Animal {} public class Lion : Animal {} var monkey = new Monkey(); var giraffe = new Giraffe(); var lion = new Lion(); IEnumerable<Animal> animals = new Animal[] { monkey, giraffe, lion }; IEnumerable<Animal> fewerAnimals = animals.NotOfType<Giraffe>(); However, I can not come up with an implementation that supports that specific calling syntax. This is what I've tried so far: public static class EnumerableExtensions { public static IEnumerable<T> NotOfType<T>(this IEnumerable<T> sequence, Type type) { return sequence.Where(x => x.GetType() != type); } public static IEnumerable<T> NotOfType<T, TExclude>(this IEnumerable<T> sequence) { return sequence.Where(x => !(x is TExclude)); } } Calling these methods would look like this: // Animal is inferred IEnumerable<Animal> fewerAnimals = animals.NotOfType(typeof(Giraffe)); and // Not all types could be inferred, so I have to state all types explicitly IEnumerable<Animal> fewerAnimals = animals.NotOfType<Animal, Giraffe>(); I think that there are major drawbacks with the style of both of these calls. The first one suffers from a redundant "of type/type of" construct, and the second one just doesn't make sense (do I want a list of animals that are neither Animals nor Giraffes?). So, is there a way to accomplish what I want? If not, could it be possible in future versions of the language? (I'm thinking that maybe one day we will have named type arguments, or that we only need to explicitly supply type arguments that can't be inferred?) Or am I just being silly?

    Read the article

  • What are the virtues of using XML comments in .NET?

    - by Michal Czardybon
    I can't understand the virtues of using XML comments. I know they can be converted into nice documentation external to the code, but the same can be achieved with the much more concise DOxygen syntax. In my opinion the XML comments are wrong, because: They obfuscate the comments and the code in general. (They are more difficult to read by humans). Less code can be viewed on a single screen, because "summary" and "/summary" take additional lines. They suggest that all method parameters have to be commented, whereas 90% of them are obvious and SHOULD be left not commented. The only problem I have with this is that my point of view seems to be in minority. Why?

    Read the article

  • Why are only some of my attributes shown in the response xml of jaxws?

    - by Andreas
    I created a jaxws webservice, but it returns only some of the attributes of my objects in the response xml. E.g. public class MyObject { private String attribute1; private String attribute2; //getter and setter } But the returned XML only contains <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"> <soap:Body> <ns2:getVariantsResponse xmlns:ns2="mynamespace"> <myObject> <attribute1>stringcontent</attribute1> </myObject> ....

    Read the article

  • Can I clone an IQueryable in linq? For UNION purposes?

    - by user169867
    I have a table of WorkOrders. The table has a PrimaryWorker & PrimaryPay field. It also has a SecondaryWorker & SecondaryPay field (which can be null). I wish to run 2 very similar queries & union them so that it will return a Worker Field & Pay field. So if a single WorkOrder record had both the PrimaryWorker and SecondaryWorker field populated I would get 2 records back. The "where clause" part of these 2 queries is very similar and long to construct. Here's a dummy example var q = ctx.WorkOrder.Where(w => w.WorkDate >= StartDt && w.WorkDate <= EndDt); if(showApprovedOnly) { q = q.Where(w => w.IsApproved); } //...more filters applied Now I also have a search flag called "hideZeroPay". If that's true I don't want to include the record if the worker was payed $0. But obviously for 1 query I need to compare the PrimaryPay field and in the other I need to compare the SecondaryPay field. So I'm wondering how to do this. Can I clone my base query "q" and make a primary & secondary worker query out of it and then union those 2 queries together? I'd greatly appreciate an example of how to correctly handle this. Thanks very much for any help.

    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 | 174 175 176 177 178 179 180 181 182 183 184 185  | Next Page >