You need to say query = query.Where(x => x.STUDENT_LAST_NAME.StartsWith(“Lewis”)); instead of just query.Where(x => x.STUDENT_LAST_NAME.StartsWith(“Lewis”)); 2 solved LINQ ignoring where clause with method syntax [duplicate]
Though the other answers supplied are effective enough, I would like to supply a thorough answer to assist at more than just the current syntactical level of C#. For example; Linq wasn’t available prior to 3.5. IS Keyword Checks if an object is compatible with a given type, or (starting with C# 7.0) tests an … Read more
The problem is that you need to provide a lambda expression for the second argument of ToDictionary. ToDictionary also returns a Dictionary<T, U> so you won’t be able to assign it to an instance of ConcurrentDictionary<T, U>. This should do the trick: var dicFailedProxies = File.ReadLines(“failed_proxies.txt”) .Distinct() .ToDictionary(line => line, line => 0); Of course, … Read more
Try this: List<tblUsersTypeC> usertype = userToInsertList.Select(o => new tblUsersTypeC() { isPrivite = ((o.Counts.FollowedBy + o.Counts.Follows + o.Counts.Media) == 0), UserName = o.Username, WebsiteUrl = o.Website }).ToList(); 4 solved cannot convert from ‘void’ to ‘project.Models.tblUserTypes.tblUsersTypeC’
You can solve your problem by grouping objects by Id1 and Id2. By the way, you sould share the test model and initialize the collection on problem definition next time ? internal class TestModel { public TestModel(string id1, string id2, string value) { Id1 = id1; Id2 = id2; Value = value; } public string … Read more
var result = studentList .Join(markList, m => m.Id, s => s.Sid, (s, m) => new { s, m }) .GroupBy(t => t.s) .Select(g => new { Student = g.Key, MarksCount = g.Count(), Marks = g.Select(x => x.m).ToList() }) .ToList(); MarksCount – total marks for this student Marks – List of marks for this student solved … Read more
It should be something like this (Use SelectMany and Count methods): int c = elements.SelectMany(e => e.Attributes) .Count(a => a.Name == “City” && a.GetValue().ToString() == “Oakland”); 0 solved How to write this nested foreach loop query in LINQ?
If you want to filter the files you are gonna iterate through, you can use System.IO‘s FileInfo class instead if File. Then you filter the files by their CreationDate property: DateTime yourstartDate = new DateTime(); DateTime yourEndDate = new DateTime(); DirectoryInfo di = new DirectoryInfo(“any_directory”); List<FileInfo> fis = di.GetFiles().Where(x => x.CreationTime >= yourstartDate && x.CreationTime … Read more
Your code can be since just copy and pasted and that should never be your first thought of what to do, for example, this is all your doing to generate a string so you can just call this code in each of your sequences. private string GenerateString(int idx) { var stringChars = new char[26]; var … Read more
Try my solution, string xml = @”<categories> <category> <id>1</id> <name>Computer</name> <description>Information tech.</description> <active>False</active> </category> <category> <id>2</id> <name>Cate1</name> <description>MMukh</description> <active>True</active> </category> </categories>”; XDocument xDoc = XDocument.Parse(xml); int id = 1; var items = xDoc.XPathSelectElement(“//category[id=” + id + “]”) .Elements() .ToDictionary(e => e.Name.LocalName, e => (string)e); if (items != null) { // display these fields to the … Read more
If _ProjectContext.ProjectDetails has more then one phase item then it will throw exception. But if there is no matching element then it will return 0 var numbers = new[] {1 ,2, 3}; numbers.Where(x => x == 6).SingleOrDefault(); // returns 0 because default(int) == 0 1 solved In c# where in clause works for integers?
Two options to consider: Use dynamic typing to call a generic method which will return you a Func<object, object> which you can use later by wrapping up an expression-tree-compiled delegate: public Func<Object, Object> CreateFunc(object sampleValue) { dynamic dynamicValue = sampleValue; return CreateFuncImpl(dynamicValue); // Dynamic type inference } private Func<Object, Object> CreateFuncImpl<T>(T sampleValue) { // You … Read more
I think it is easier to translate SQL using query comprehension syntax instead of lambda syntax. General rules: Translate inner queries into separate query variables Translate SQL phrases in LINQ phrase order Use table aliases as range variables, or if none, create range variables from table names abbreviations Translate IN to Contains Translate SQL functions … Read more
“Find the items from the model’s property “MenuItems” that has a category name equal to category.name” It is like a filter on the list MenuItems 5 solved What does LINQ query .Where() do?
You have not initialized MyDataTable by a data after instantiation, you have filled in data set but not a data table. So just try out MyDataSet.Tables[0] instead of MyDataTable.AsEnumerable() // DataSet filled in but data table still empty! MyDataAdapter.Fill(MyDataSet,”STUFF”); 1 solved Reading A Fixed Format Text File – Part 3