Posts Tagged ‘LINQ’

Design Guidelines for LINQ

Have you wondered if and when you should use the new LINQ features in .Net 3.5? Like, where should I put a new extension method? Should I use Func<T> or a custom delegate? How do I best implement a mix-in (extension methods on an interface)? Well, Mircea Trofin has just published a new draft of [...]

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How to Update Data with LINQ-to-SQL

When learning LINQ-to-SQL, it’s not immediately obvious how to do an update. Querying is easy, and there are methods for inserting and deleting. Updating usually occurs by modifying an object already known to the DataContext and then calling SubmitChanges on the context. var product = (from p in dataContext.Products where p.ProductID == 1 select p).Single(); [...]

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How to See the SQL Generated by a LINQ to SQL Command

Quick tip: If you want to see the SQL generated by LINQ to SQL for a query or command, simply set the Log property of your generated DataContext class to an instance of a TextReader. If this is your code: using System; using System.Linq; using System.Data.Linq; namespace LINQtoSQLConsole { class Program { static void Main(string[] [...]

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How to Use Grouping in C# LINQ Syntax

When you started using LINQ, did you think it looked like SQL? I did. The more I learned LINQ, the more I realized it wasn’t anything like SQL. Take grouping, for example. Because LINQ has a group by statement, and it looks like SQL, I assumed that the syntax for grouping in LINQ would be [...]

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LINQ to DataSets – the Missing Manual

Last week I had to prepare a small presentation for a new LINQ workshop. For my research, I browsed through the MSDN documentation on LINQ where I came across a reference to "LINQ to DataSets". I couldn’t find any more information about it though, and so LINQ to DataSets got a small mention in my [...]

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Using LinqPad to Create a Time-Selector Drop-Down List

I am really getting into LINQ now! I think it’s fantastic. I recently wanted to develop a quick drop-down list in ASP.Net which allows a user to select a time of day from a list. The times are 15 minutes apart, so the list would look like this: … 08:00 08:15 08:30 08:45 09:00 … [...]

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