usr/local/share/dotnet/sdk"; var fileList = Directory.GetFiles(startFolder, "*.*", SearchOption.AllDirectories); var fileQuery = from file in fileList let fileLen = new FileInfo(file).Length where fileLen > 0 select fileLen; // Cache the results to avoid multiple trips to the...
.Select(y => y.FirstOrDefault()) FirstOrDefault()means: Returns the first element of a sequence, or a default value if no element is found. It will filter your data,so you can't get all the records for each postId. I suggest you could delete it. ...
Some query operations must be expressed as a method call. The most common such methods are those methods that return singleton numeric values, such asSum,Max,Min,Average, and so on. These methods must always be called last in any query because they return a single value and can't serve as...
(',') where Convert.ToInt32(splitName[2]) == Convert.ToInt32(splitScoreLine[0]) select (FirstName: splitName[0], LastName: splitName[1], ExamScores: (from scoreAsText in splitScoreLine.Skip(1) select Convert.ToInt32(scoreAsText)) .ToList() ); // Display each student's name ...
select allows the projection of an entire element from the collection, the construction of a new type with parts of that element and other calculated values, or a subcollection of items into the result. The messageQueue collection is of type System.Messaging.MessageQueue, which implements the IEnu...
How to find and search list values which is available or not from multiple another lists. For example, List<string> FromList = new List<string>() { "Sub A", "Sub B" }; List<string> List1 = new List<string>() { "Sub A=80", "Sub D=70" }; ...
Note that the Select method has multiple overloaded versions. After running this code, selectResults contains a list of values resembling the following: 1. Howard Snyder 2. Yoshi Latimer 3. John Steel 4. Jaime Yorres 5. Fran Wilson 6. Rene Phillips 7. Paula Wilson 8. Jose Pavarotti 9. ...
linq18: SelectMany - Multiple from //c# public void Linq18() { List<Customer> customers = GetCustomerList(); DateTime cutoffDate = new DateTime(1997, 1, 1); var orders = from c in customers where c.Region == "WA" from o in c.Orders where o.OrderDate >= cutoffDate select new {...
Sorting with null values Creating Range() Repeat() Comparing and Combining Intersect Except Concat Distinct Union Projection Select() Join() SelectMany() Totaling Sum operator Grouping and Summing GroupBy(Single property) GroupBy(Multiple Properties) ...
I'm not going to try to explain this method, other than to say it essentially builds a predicate expression for all the values using the valueSelector (i.e. p => p.Firstname) and ORs those predicates together to create an expression for the complete predicate. For more...