.net-4.5

问题 I am working with .NET4.5 and VS2013, I have this query that gets dynamic result from db. dynamic topAgents = this._dataContext.Sql( "select t.create_user_id as \"User\", sum(t.netamount) as \"Amount\" from transactiondetail t where t.update_date > sysdate -7 group by t.create_user_id") .QueryMany<dynamic>(); Following statement fails with compilation error Cannot use a lambda expression as an argument to a dynamically dispatched operation without first casting it to a delegate or expression

问题 This is in the context of Web Services (client end). I need to interface with a back-end system (Java) and it is a requirement to transmit some control characters in the &#14; and &#31; range. I'm well aware that XML 1.0 doesn't support this, but am interested to know if the .NET 4 platform or .NET 4.5 web services framework support conversations in XML 1.1. 回答1: No, it doesn't look like XmlReader (the core of much of the XML support in .NET) supports 1.1: using System; using System.IO; using

问题 This is follow up question to : Infinite IObservable from Task function and toggle observable Above question asks if it is possible to create a repeating IObservable<TResult> from IObservable<bool> toggle and Task<TResult> query , so that query is called repeatedly if last toggle was true and not called at all if last toggle is false . That seems to be pretty easily achieved using Defer and Switch methods. But that has problem, because the query is not parametrized. Concretely, there are two

问题 Following this, could anyone post a barebone solution for the following task, targeting .NET 4.5 (and WPF UI on a bigger scale)? Basically I'm looking for a functional analog of any torrent application implemented on .NET 4.5 and c#. The task: I have IEnumerable<IProcessable> , containing 1000 instances of IProcessable , IProcessable has Process(int argument) method, taking from 1 to 10 seconds to execute. I want to loop through the collection and process each instance of IProcessable ,

问题 This question already has answers here : Possible to use ?? (the coalesce operator) with DBNull? (6 answers) Closed 5 years ago . I'm getting DBNull results from DB. Trying to apply ?? operator to it like result["field1"] ?? result["field2"] field1 = DBNull field2 = 4 but it doesn't work, returns {} because result["field1"] is not null (it's DBNull). I expect to get that 4 from it. Tried to do result["field1"] = null first, but it doesn't work, it's still DBNull type. The question is how to

问题 I am using a Telerik combobox but I think the question is relevant to the standard wpf combobox. The control is bound to an observable collection of “TableRecord” where this object looks like this: public enum RecordState { Orginal, Added, Modified, Deleted } public class TableRecord<T> { public Guid Id { get; set; } public string DisplayName { get; set; } public T Record { get; set; } public RecordState State { get; set; } public TableRecord(Guid id, string displayName, T record, RecordState

问题 ArrayList , which I use in legacy Compact Framework code, does not seem to be available in newfangled (.NET 4.5.1) code. I am storing instances of custom classes in it. What is a good replacement for it - List<Object> , or is there something more suitable? 回答1: As @HighCore mentioned in his comment, you should use the generic form of List, List<T> . If you have several classes defined that you need to include in that List, they probably have common properties, methods. In that case, you can

问题 Let's say I have a class from a 3rd-party, which is a data-model. It has perhaps 100 properties (some with public setters and getters, others with public getters but private setters). Let's call this class ContosoEmployeeModel I want to facade this class with an interface (INavigationItem, which has Name and DBID properties) to allow it to be used in my application (it's a PowerShell provider, but that's not important right now). However, it also needs to be usable as a ContosoEmployeeModel.

问题 I have a simple page. On load, it calls a web service, and then I get the following error: an attempt was made to call the method using a GET request, which is not allowed My JS-code: function getTutors() { var url = '<%= ResolveUrl("~/services/tutorservice.asmx/gettutors") %>'; $.ajax({ type: "GET", data: "{'data':'" + 'test-data' + "'}", url: url, contentType: "application/json; charset=utf-8", dataType: "json", success: function (d) { alert('succes'); return d; }, error: function () {

问题 I have simple function to write files. public static void WriteFile(string filename, string text) { StreamWriter file = new StreamWriter(filename); try { file.Write(text); } catch (System.UnauthorizedAccessException) { MessageBox.Show("You have no write permission in that folder."); } catch (System.Exception e) { MessageBox.Show(e.Message); } file.Close(); } How can I convert my code to use StreamWriter.WriteAsync with try-catch? 回答1: async public static void WriteFile(string filename, string