Search Results

Search found 6205 results on 249 pages for 'linq to nhibernate'.

Page 160/249 | < Previous Page | 156 157 158 159 160 161 162 163 164 165 166 167  | Next Page >

  • Expression Tree with Property Inheritance causes an argument exception

    - by Adam Driscoll
    Following this post: link text I'm trying to create an expression tree that references the property of a property. My code looks like this: public interface IFoo { void X {get;set;} } public interface IBar : IFoo { void Y {get;set;} } public interface IFooBarContainer { IBar Bar {get;set;} } public class Filterer { //Where T = "IFooBarContainer" public IQueryable<T> Filter<T>(IEnumerable<T> collection) { var argument = Expression.Parameter(typeof (T), "item"); //... //where propertyName = "IBar.X"; PropertyOfProperty(argument, propertyName); } private static MemberExpression PropertyOfProperty(Expression expr, string propertyName) { return propertyName.Split('.').Aggregate<string, MemberExpression>(null, (current, property) => Expression.Property(current ?? expr, property)); } } I receive the exception: System.ArgumentException: Instance property 'X' is not defined for type 'IBar' ReSharper turned the code in the link above into the condensed statement in my example. Both forms of the method returned the same error. If I reference IBar.Y the method does not fail.

    Read the article

  • ASP.net displaying data from SQL data source

    - by c11ada
    hey all, im using linq2SQL to grab information from my SQL database, i have a gridview which shows all the top level information, in this case a list of groups (i.e admin, users and so on) when a user clicks say the admin group, i want to be able to show each member in that group, i have the following code which grabs the information from the database, DataClassesDataContext dc = new DataClassesDataContext(); GridViewRow row = GridView1.SelectedRow; var query1 = from p in dc.Users where p.groups.GroupID == Int32.Parse(row.Cells[1].Text) select new { p.Name, p.Address, p.Contact Number, p.Bio, }; i no i can use gridview again to display the results of the query, but this doesnt really look nice as it shows too much information at one, how would i go about having some sort of display which will show just one user at a time giving me the chance to click next and back ? thanks

    Read the article

  • Why can't I insert record with foregion key in a single server request?

    - by Eran Betzalel
    I'm tryring to do a simple insert with foregion key, but it seems that I need to use db.SaveChanges() for every record insert. How can I manage to use only one db.SaveChanges() at the end of this program? foreach (var file in files) { db.AddToFileSet(file); db.SaveChanges(); db.AddToDirectorySet( new GlxCustomerPhone { SimIdentifier = file.Name + "Dir", CreationDate = DateTime.UtcNow, file_relation = file }); db.SaveChanges(); }

    Read the article

  • Change C# sorting behaviour

    - by Erik
    Lets say i have the strings abc_ and abc2_. Now, normally when sorting i C# abc2_ would come after abc_, leaving the result: abc_ abc2_ I am using this to sort, if it matters: var element = from c in elements orderby c.elementName ascending select c; How can i change this? I want abc_ to come last. Reversing is not an option because the list is contains more than two elements.

    Read the article

  • Xml failing to deserialise

    - by Carnotaurus
    I call a method to get my pages [see GetPages(String xmlFullFilePath)]. The FromXElement method is supposed to deserialise the LitePropertyData elements to strongly type LitePropertyData objects. Instead it fails on the following line: return (T)xmlSerializer.Deserialize(memoryStream); and gives the following error: <LitePropertyData xmlns=''> was not expected. What am I doing wrong? I have included the methods that I call and the xml data: public static T FromXElement<T>(this XElement xElement) { using (var memoryStream = new MemoryStream(Encoding.ASCII.GetBytes(xElement.ToString()))) { var xmlSerializer = new XmlSerializer(typeof(T)); return (T)xmlSerializer.Deserialize(memoryStream); } } public static List<LitePageData> GetPages(String xmlFullFilePath) { XDocument document = XDocument.Load(xmlFullFilePath); List<LitePageData> results = (from record in document.Descendants("row") select new LitePageData { Guid = IsValid(record, "Guid") ? record.Element("Guid").Value : null, ParentID = IsValid(record, "ParentID") ? Convert.ToInt32(record.Element("ParentID").Value) : (Int32?)null, Created = Convert.ToDateTime(record.Element("Created").Value), Changed = Convert.ToDateTime(record.Element("Changed").Value), Name = record.Element("Name").Value, ID = Convert.ToInt32(record.Element("ID").Value), LitePageTypeID = IsValid(record, "ParentID") ? Convert.ToInt32(record.Element("ParentID").Value) : (Int32?)null, Html = record.Element("Html").Value, FriendlyName = record.Element("FriendlyName").Value, Properties = record.Element("Properties") != null ? record.Element("Properties").Element("LitePropertyData").FromXElement<List<LitePropertyData>>() : new List<LitePropertyData>() }).ToList(); return results; } Here is the xml: <?xml version="1.0" encoding="utf-8"?> <root> <rows> <row> <ID>1</ID> <ImageUrl></ImageUrl> <Html>Home page</Html> <Created>01-01-2012</Created> <Changed>01-01-2012</Changed> <Name>Home page</Name> <FriendlyName>home-page</FriendlyName> </row> <row xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <Guid>edeaf468-f490-4271-bf4d-be145bc6a1fd</Guid> <ID>8</ID> <Name>Unused</Name> <ParentID>1</ParentID> <Created>2006-03-25T10:57:17</Created> <Changed>2012-07-17T12:24:30.0984747+01:00</Changed> <ChangedBy /> <LitePageTypeID xsi:nil="true" /> <Html> What is the purpose of this option? This option checks the current document for accessibility issues. It uses Bobby to provide details of whether the current web page conforms to W3C's WCAG criteria for web content accessibility. Issues with Bobby and Cynthia Bobby and Cynthia are free services that supposedly allow a user to expose web page accessibility barriers. It is something of a guide but perhaps a blunt instrument. I tested a few of the webpages that I have designed. Sure enough, my pages fall short and for good reason. I am not about to claim that Bobby and Cynthia are useless. Although it is useful and commendable tool, it project appears to be overly ambitious. Nevertheless, let me explain my issues with Bobby and Cynthia: First, certain W3C standards for designing web documents are often too strict and unworkable. For instance, in some versions W3C standards for HTML, certain tags should not include a particular attribute, whereas in others they are requisite if the document is to be ???well-formed???. The standard that a designer chooses is determined usually by the requirements specification document. This specifies which browsers and versions of those browsers that the web page is expected to correctly display. Forcing a hypertext document to conform strictly to a specific W3C standard for HTML is often no simple task. In the worst case, it cannot conform without losing some aesthetics or accessibility functionality. Second, the case of HTML documents is not an isolated case. Standards for XML, XSL, JavaScript, VBScript, are analogous. Therefore, you might imagine the problems when you begin to combine these languages and formats in an HTML document. Third, there is always more than one way to skin a cat. For example, Bobby and Cynthia may flag those IMG tags that do not contain a TITLE attribute. There might be good reason that a web developer chooses not to include the title attribute. The title attribute has a limited numbers of characters and does not support carriage returns. This is a major defect in the design of this tag. In fact, before the TITLE attribute was supported, there was the ALT attribute. Most browsers support both, yet they both perform a similar function. However, both attributes share the same deficiencies. In practice, there are instances where neither attribute would be used. Instead, for example, the developer would write some JavaScript or VBScript to circumvent these deficiencies. The concern is that Bobby and Cynthia would not notice this because it does not ???understand??? what the JavaScript does. </Html> <FriendlyName>unused</FriendlyName> <IsDeleted>false</IsDeleted> <Properties> <LitePropertyData> <Description>Image for the page</Description> <DisplayEditUI>true</DisplayEditUI> <OwnerTab>1</OwnerTab> <DisplayName>Image Url</DisplayName> <FieldOrder>1</FieldOrder> <IsRequired>false</IsRequired> <Name>ImageUrl</Name> <IsModified>false</IsModified> <ParentPageID>3</ParentPageID> <Type>String</Type> <Value xsi:type="xsd:string">smarter.jpg</Value> </LitePropertyData> <LitePropertyData> <Description>WebItemApplicationEnum</Description> <DisplayEditUI>true</DisplayEditUI> <OwnerTab>1</OwnerTab> <DisplayName>WebItemApplicationEnum</DisplayName> <FieldOrder>1</FieldOrder> <IsRequired>false</IsRequired> <Name>WebItemApplicationEnum</Name> <IsModified>false</IsModified> <ParentPageID>3</ParentPageID> <Type>Number</Type> <Value xsi:type="xsd:string">1</Value> </LitePropertyData> </Properties> <Seo> <Author>Phil Carney</Author> <Classification /> <Copyright>Carnotaurus</Copyright> <Description> What is the purpose of this option? This option checks the current document for accessibility issues. It uses Bobby to provide details of whether the current web page conforms to W3C's WCAG criteria for web content accessibility. Issues with Bobby and Cynthia Bobby and Cynthia are free services that supposedly allow a user to expose web page accessibility barriers. It is something of a guide but perhaps a blunt instrument. I tested a few of the webpages that I have designed. Sure enough, my pages fall short and for good reason. I am not about to claim that Bobby and Cynthia are useless. Although it is useful and commendable tool, it project appears to be overly ambitious. Nevertheless, let me explain my issues with Bobby and Cynthia: First, certain W3C standards for designing web documents are often too strict and unworkable. For instance, in some versions W3C standards for HTML, certain tags should not include a particular attribute, whereas in others they are requisite if the document is to be ???well-formed???. The standard that a designer chooses is determined usually by the requirements specification document. This specifies which browsers and versions of those browsers that the web page is expected to correctly display. Forcing a hypertext document to conform strictly to a specific W3C standard for HTML is often no simple task. In the worst case, it cannot conform without losing some aesthetics or accessibility functionality. Second, the case of HTML documents is not an isolated case. Standards for XML, XSL, JavaScript, VBScript, are analogous. Therefore, you might imagine the problems when you begin to combine these languages and formats in an HTML document. Third, there is always more than one way to skin a cat. For example, Bobby and Cynthia may flag those IMG tags that do not contain a TITLE attribute. There might be good reason that a web developer chooses not to include the title attribute. The title attribute has a limited numbers of characters and does not support carriage returns. This is a major defect in the design of this tag. In fact, before the TITLE attribute was supported, there was the ALT attribute. Most browsers support both, yet they both perform a similar function. However, both attributes share the same deficiencies. In practice, there are instances where neither attribute would be used. Instead, for example, the developer would write some JavaScript or VBScript to circumvent these deficiencies. The concern is that Bobby and Cynthia would not notice this because it does not ???understand??? what the JavaScript does. </Description> <Keywords>unused</Keywords> <Title>unused</Title> </Seo> </row> </rows> </root> EDIT Here are my entities: public class LitePropertyData { public virtual string Description { get; set; } public virtual bool DisplayEditUI { get; set; } public int OwnerTab { get; set; } public virtual string DisplayName { get; set; } public int FieldOrder { get; set; } public bool IsRequired { get; set; } public string Name { get; set; } public virtual bool IsModified { get; set; } public virtual int ParentPageID { get; set; } public LiteDataType Type { get; set; } public object Value { get; set; } } [Serializable] public class LitePageData { public String Guid { get; set; } public Int32 ID { get; set; } public String Name { get; set; } public Int32? ParentID { get; set; } public DateTime Created { get; set; } public String CreatedBy { get; set; } public DateTime Changed { get; set; } public String ChangedBy { get; set; } public Int32? LitePageTypeID { get; set; } public String Html { get; set; } public String FriendlyName { get; set; } public Boolean IsDeleted { get; set; } public List<LitePropertyData> Properties { get; set; } public LiteSeoPageData Seo { get; set; } /// <summary> /// Saves the specified XML full file path. /// </summary> /// <param name="xmlFullFilePath">The XML full file path.</param> public void Save(String xmlFullFilePath) { XDocument doc = XDocument.Load(xmlFullFilePath); XElement demoNode = this.ToXElement<LitePageData>(); demoNode.Name = "row"; doc.Descendants("rows").Single().Add(demoNode); doc.Save(xmlFullFilePath); } }

    Read the article

  • "Row not found or changed" Problem

    - by winston schröder
    Hi there, I'm working on a SQL CE Database and get into the "Row nor found or changed" exception. The exception only occurs when I try to update. On the first Run after the insert it shows up a MemberChangeConflict which says, that my Column Created_at has in all three values (current, original, database) the same. But in a second attempt it doesn't appear anymore. The DataContext is instanciated on Startup and freed on Exit of my Local(!) Application. I use a sqlmetal generated mapping and code file. In the map I added some Associations and set the timemstamp columns UpdateCheck property to Always while all other have the setting never. The Timestamp Column is marked as isVersion="true", the Id Column as Primary Key. Since I don't dispose the datacontext I expected to be using implicit transaction. When I run the SubmitChanges Method within a TransactionScope. Can anyone tell me how I can update the timestamp within the code ? I know about the Problems one has to deal with if you dispose the datacontext. So I decided not to do this since I use a Single User Local DB Cache File. (I did already use a version where I disposed the datacontext after every usage, but this version had a real bad performance and error rate, so I decided to choose the other variant.) LibDB.Client.Vehicles tmp = null; try { tmp = e.Parameter as LibDB.Client.Vehicles; if (tmp == null) return; if (!this._dc.Vehicles.Contains(tmp)) { this._dc.Vehicles.Attach(tmp); } this.ShowChangesReport(this._dc.GetChangeSet()); using (TransactionScope ts = new TransactionScope()) { try { this._dc.SubmitChanges(); ts.Complete(); } catch (ChangeConflictException cce) { Console.WriteLine("Optimistic concurrency error."); Console.WriteLine(cce.Message); Console.ReadLine(); foreach (ObjectChangeConflict occ in this._dc.ChangeConflicts) { MetaTable metatable = this._dc.Mapping.GetTable(occ.Object.GetType()); LibDB.Client.Vehicles entityInConflict = (LibDB.Client.Vehicles)occ.Object; Console.WriteLine("Table name: {0}", metatable.TableName); Console.Write("Vin: "); Console.WriteLine(entityInConflict.Vin); foreach (MemberChangeConflict mcc in occ.MemberConflicts) { object currVal = mcc.CurrentValue; object origVal = mcc.OriginalValue; object databaseVal = mcc.DatabaseValue; MemberInfo mi = mcc.Member; Console.WriteLine("Member: {0}", mi.Name); Console.WriteLine("current value: {0}", currVal); Console.WriteLine("original value: {0}", origVal); Console.WriteLine("database value: {0}", databaseVal); } throw cce; } } catch (Exception ex) { this.ShowChangeConflicts(this._dc.ChangeConflicts); Console.WriteLine(ex.Message); } } this.ShowChangesReport(this._dc.GetChangeSet());

    Read the article

  • How to apply global filter on Entity Framework?

    - by Hernan
    I have a table in my model named Customers with a field IsActive. Whenever I run a query on Customers, only the active customers should be retrieved. I can include the filter in every query, but that doesn't look very. I would like to be able to override the Customers property at the Object Context lever, but I am not sure if this is possible. Any help would be very appreciated! Thanks

    Read the article

  • Get correct output from UTF-8 stored in VarChar using Entity Framework or Linq2SQL?

    - by jasonpenny
    Borland StarTeam seems to store its data as UTF-8 encoded data in VarChar fields. I have an ASP.NET MVC site that returns some custom HTML reports using the StarTeam database, and I would like to find a better solution for getting the correct data, for a rewrite with MVC2. I tried a few things with Encoding GetBytes and GetString, but I couldn't get it to work (we use mostly Delphi at work); then I figured out a T-SQL function to return a NVarChar from UTF-8 stored in a VarChar, and created new SQL views which return the data as NVarChar, but it's slow. The actual problem appears like this: “description†instead of “description”, in both SSMS and in a webpage when using Linq2SQL Is there a way to get the proper data out of these fields using Entity Framework or Linq2SQL?

    Read the article

  • asp.net mvc insert doesnt seem to work for me....

    - by Pandiya Chendur
    My controller's call to repository insert method all the values are passed but it doesn't get inserted in my table.. My controller method, [AcceptVerbs(HttpVerbs.Post)] public ActionResult Create([Bind(Exclude = "Id")]FormCollection collection) { try { MaterialsObj materialsObj = new MaterialsObj(); materialsObj.Mat_Name = collection["Mat_Name"]; materialsObj.Mes_Id = Convert.ToInt64(collection["MeasurementType"]); materialsObj.Mes_Name = collection["Mat_Type"]; materialsObj.CreatedDate = System.DateTime.Now; materialsObj.CreatedBy = Convert.ToInt64(1); materialsObj.IsDeleted = Convert.ToInt64(1); consRepository.createMaterials(materialsObj); return RedirectToAction("Index"); } catch { return View(); } } and my repository, public MaterialsObj createMaterials(MaterialsObj materialsObj) { Material mat = new Material(); mat.Mat_Name = materialsObj.Mat_Name; mat.Mat_Type = materialsObj.Mes_Name; mat.MeasurementTypeId = materialsObj.Mes_Id; mat.Created_Date = materialsObj.CreatedDate; mat.Created_By = materialsObj.CreatedBy; mat.Is_Deleted = materialsObj.IsDeleted; db.Materials.InsertOnSubmit(mat); return materialsObj; } What am i missing here any suggestion....

    Read the article

  • Sorting List which has object that contains two string members that contains numbers

    - by Lemo
    I want to know the best solution for this my case here is that i am taking values from Excel sheet and pushing them to database field, sometimes that field might contain some strings (thats why I cant make my object members int / double) In my class below size is the variable responsible for showing size of files in bytes public class dataNameValue { public string Name { get; set; } public string Count { get; set; } public string Size { get; set; } } I wanted to sort the list by file Size something like List mylist = new List(); mylist = mylist.OrderByDescending(i = i.Size).ToList(); The problem is that if i sorted it without converting it to "int/double" first -- its not giving right results

    Read the article

  • Problem with interface implementation in partial classes.

    - by Bas
    I have a question regarding a problem with L2S, Autogenerated DataContext and the use of Partial Classes. I have abstracted my datacontext and for every table I use, I'm implementing a class with an interface. In the code below you can see I have the Interface and two partial classes. The first class is just there to make sure the class in the auto-generated datacontext inherets Interface. The other autogenerated class makes sure the method from Interface is implemented. namespace PartialProject.objects { public interface Interface { Interface Instance { get; } } //To make sure the autogenerated code inherits Interface public partial class Class : Interface { } //This is autogenerated public partial class Class { public Class Instance { get { return this.Instance; } } } } Now my problem is that the method implemented in the autogenerated class gives the following error: - Property 'Instance' cannot implement property from interface 'PartialProject.objects.Interface'. Type should be 'PartialProjects.objects.Interface'. <- Any idea how this error can be resolved? Keep in mind that I can't edit anything in the autogenerated code. Thanks in advance!

    Read the article

  • Problem Writing Linq2Xml Query

    - by Gavin Draper
    I'm trying to write a Linq2XML query to query the following XML. I need it to pull back all photos for a given GalleryID. <Albums> <Album GalleryId="1" Cover="AlbumCover1.jpg" Title="Album 1"> <Photos> <Photo Title="Image1" URL="img1.jpg" DateAdded="01/01/2010 09:20"/> <Photo Title="Image2" URL="img2.jpg" DateAdded="01/01/2010 09:20"/> <Photo Title="Image3" URL="img3.jpg" DateAdded="01/01/2010 09:20"/> </Photos> </Album> <Album GalleryId="2" Cover="AlbumCover1.jpg" Title="Album 2"> <Photos> <Photo Title="Image1" URL="img1.jpg" DateAdded="01/01/2010 09:20"/> <Photo Title="Image2" URL="img2.jpg" DateAdded="01/01/2010 09:20"/> </Photos> </Album> </Albums> The best I've come up with is XDocument xmlDoc = XDocument.Load(GalleryFilePath); var x = from c in xmlDoc.Descendants("Album") where c.Attribute("GalleryId").Equals(GalleryId) orderby c.Attribute("Title").Value descending select new { Title = c.Element("Photo").Attribute("Title"), URL = c.Element("Photo").Attribute("URL"), DateAdded = c.Element("Photo").Attribute("DateAdded") }; This returns nothing, I'm guessing this is because I'm telling it to query the Album element then trying to loop through the photo elements. Any tips as to how this should be done? Thanks

    Read the article

  • How do I simulate "Is In" using Linq2Sql

    - by flipdoubt
    I often find myself with a list of disconnected Linq2Sql objects or keys that I need to re-select from a Linq2Sql data-context to update or delete in the database. If this were SQL, I would use IS IN in the SQL WHERE clause, but I am stuck with what to do in Linq2Sql. Here is a sample of what I would like to write: public void MarkValidated(IList<int> idsToValidate) { using(_Db.NewSession()) // Instatiates new DataContext { // ThatAreIn <- this is where I am stuck var items = _Db.Items.ThatAreIn(idsToValidate).ToList(); foreach(var item in items) item.Validated = DateTime.Now; _Db.SubmitChanges(); } // Disposes of DataContext } Or: public void DeleteItems(IList<int> idsToDelete) { using(_Db.NewSession()) // Instatiates new DataContext { // ThatAreIn <- this is where I am stuck var items = _Db.Items.ThatAreIn(idsToValidate); _Db.Items.DeleteAllOnSubmit(items); _Db.SubmitChanges(); } // Disposes of DataContext } Can I get this done in one trip to the database? If so, how? Is it possible to send all those ints to the database as a list of parameters and is that more efficient than doing a foreach over the list to select each item one at a time?

    Read the article

  • C# XElement: Node Formatting with HTML

    - by Arnej65
    I'm extracting XML node from an XElement. When I use XElement.Value it strips any HTML that may be in the node. I know that if I do XElement.ToString() I can keep the HTML, but it also gives me the node tags. Is there any way to extract the content of a Node as is without the HTML being stripped out? Cheers.

    Read the article

  • Is there an easy way to compare if 2 XDocuments are equal ignoring element/attribute order?

    - by Davy8
    Unit testing my serialization code I found one failed because I had attributes listed in a different order (I'm just comparing the XDocument.ToString() values) and while I could fix that, it really doesn't matter to me in what order the elements or attributes appear as long as they're all there with the right name at the right level of hierarchy. I could probably write a method do this, but I'm wondering if there's an easy built in way I'm not aware of.

    Read the article

  • Linqify this: Aggregate a subset of a list

    - by JMarsch
    Suppose I have a list or array of items, and I want to sum a subset of the items in the list. (in my case, it happens to always be a sequential subset). Here's the old-fashioned way: int sum = 0; for(int i = startIndex; i <= stopIndex; i++) sum += myList[i].TheValue; return sum; What's the best way to linqify that code?

    Read the article

  • mvc fill dropdownlist

    - by user276640
    i use this code to fill dropdownlist ViewData["projectType"] = new SelectList(_dataManager.Project.ProjectTypeList(), "Id", "Name"); but what i must do if i want to use not one table column but two or more columns? for example ViewData["projectType"] = new SelectList(_dataManager.Project.ProjectTypeList(), "Id", "Name1"+"Name2");

    Read the article

  • ASP.NET GridView Sort?

    - by Curtis White
    I'm performing a query with a sort in the Selecting event of the LinqDataSource. I'm then casting my query to a list and assigning it to the result. I'm using this data source in an ASP.NET gridview. I can see the list is sorted but when the ASP.NET gridview does not seem to be respecting the sort order. How can I get the gridview to respect my default sort order?

    Read the article

  • C# Using Enumerable Range and Except with custom class to determine missing sequence number

    - by Jon
    I have a List<MyClass> The class is like this: private class MyClass { public string Name{ get; set; } public int SequenceNumber { get; set; } } I want to work out what Sequence numbers might be missing. I can see how to do this here however because this is a class I am unsure what to do? I think I can handle the except method ok with my own IComparer but the Range method I can't figure out because it only excepts int so this doesn't compile: Enumerable.Range(0, 1000000).Except(chqList, MyEqualityComparer<MyClass>); Here is the IComparer: public class MyEqualityComparer<T> : IEqualityComparer<T> where T : MyClass { #region IEqualityComparer<T> Members public bool Equals(T x, T y) { return (x == null && y == null) || (x != null && y != null && x.SequenceNumber.Equals(y.SequenceNumber)); } /// </exception> public int GetHashCode(T obj) { if (obj == null) { throw new ArgumentNullException("obj"); } return obj.GetHashCode(); } #endregion }

    Read the article

  • How can i return IEnumarable data from function in GridView with Entity FrameWork?

    - by programmerist
    protected IEnumerable GetPersonalsData() { // List personel; using (FirmaEntities firmactx = new FirmaEntities()) { var personeldata = (from p in firmactx.Personals select new { p.ID, p.Name, p.SurName }); return personeldata.AsEnumerable(); } } i wan to send GetPersonelData() into GridView DataSource. Like That: gwPersonel.DataSource = GetPersonelData(); gwPersonel.DataBind(); it monitored to me on : gwPersonel.DataBind(); this error: "The ObjectContext instance has been disposed and can no longer be used for operations that require a connection."

    Read the article

  • Precompile Lambda Expression Tree conversions as constants?

    - by Nathan
    It is fairly common to take an Expression tree, and convert it to some other form, such as a string representation (for example this question and this question, and I suspect Linq2Sql does something similar). In many cases, perhaps even most cases, the Expression tree conversion will always be the same, i.e. if I have a function public string GenerateSomeSql(Expression<Func<TResult, TProperty>> expression) then any call with the same argument will always return the same result for example: GenerateSomeSql(x => x.Age) //suppose this will always return "select Age from Person" GenerateSomeSql(x => x.Ssn) //suppose this will always return "select Ssn from Person" So, in essence, the function call with a particular argument is really just a constant, except time is wasted at runtime re-computing it continuously. Assuming, for the sake of argument, that the conversion was sufficiently complex to cause a noticeable performance hit, is there any way to pre-compile the function call into an actual constant?

    Read the article

< Previous Page | 156 157 158 159 160 161 162 163 164 165 166 167  | Next Page >