I am wondering if there are any alternatives to using the Expand key word when performing an LINQ to ADO.net Data Services query. The expand method does get me the data I am interested in, but it requires me to know all of the sub-objects that I am going to be working with in advance. My absolute preference would be that those sub-obje...
Hi I am trying to get some XML data with LINQ, but running into a problem. I am using a schema, which is set in the attribute xmlns ... <CarsForSale xmlns="http://schemas.sharplogic.net/CarSales.xsd"> <CarForSale> There are many CarForSale elements. When the schema is set and I do this... XElement doc = XElement.Load(HttpCont...
I have three TextBox controls on the page <asp:TextBox ID="TextBox1" runat="server" AutoPostBack="True" OnTextChanged="TextBox_TextChanged" TabIndex="1"> <asp:TextBox ID="TextBox2" runat="server" AutoPostBack="True" OnTextChanged="TextBox_TextChanged" TabIndex="2"> <asp:TextBox ID="TextBox3" runat="server" AutoPostBack="...
What is the best LINQ tutorial that you know of? I am starting to play with it, but I haven't found a really good source yet. Any ideas? ...
I've got a User table with a bitmask that contains the user's roles. The linq query below returns all the users whose roles include 1, 4 or 16. var users = from u in dc.Users where ((u.UserRolesBitmask & 1) == 1) || ((u.UserRolesBitmask & 4) == 4) || ((u.UserRolesBitmask & 16) == 16) ...
I'm trying to determine which records to delete from a database when a user submits a form. The page has two CheckBoxList one representing the records before modification and one after. I can easily get the selected values that need to be deleted like this... //get the items not selected that were selected before var oldSelectedItems =...
I am attempting to use linq to shape list of data into a particular shape to be returned as Json from an ajax call. Given this data: var data = new List<string>(); data.Add("One"); data.Add("Two"); data.Add("Three"); And this code: ** Which is not correct and is what needs to be fixed!! ** var shap...
I've been using this nifty LINQ to SQL tool for a data access layer in an asp.net project. I keep making changes to the underlying tables and in order for the data classes to recognize the change I have to delete and readd the table which has changed. Is there some shortcut to regenerating the data layer? ...
If I have two tables... Category and Pet. Is there a way in LINQ to SQL to make the result of the joined query map to a another strongly typed class (such as: PetWithCategoryName) so that I can strongly pass it to a MVC View? I currently have Category and Pet classes... should I make another one? Maybe I missing something here. Can a...
I have a very interesting problem on my LinqToSql model. On some of my tables i have a references to other tables and in LinqToSql this is represented by a EnitiyRef class, when you are trying to access the references table LinqToSql will load the reference from the database. On my development machine everything worked fine (the referen...
I have parsed Xml using both of the following two methods... Parsing the XmlDocument using the object model and XPath queries. XSL/T But I have never used... The Linq Xml object model that was new to .Net 3.5 Can anyone tell me the comparative effeciantly between the three alternatives? I realise that the particular usage would ...
I have a project where I am taking some particularly ugly "live" HTML and forcing it into a formal XML DOM with the HTML Agility Pack. What I would like to be able to do is then query over this with Linq to XML so that I can scrape out the bits I need. I'm using the method described here to parse the HtmlDocument into an XDocument, but...
Hello! I'm moving DB from MySQL (used ODBC) to MS SQL and I want to "translate" SQL queries to LINQ. Can someone help me with this (it should SUM Charge column for every location and group result by months): SELECT sum(case when Location="Location1" then Charge else 0 end) as Location1, sum(case when Location="Location2" then Charge el...
I have 2 collections which have an Email property in both collections. I need to get a list of the items in the first list where the Email does not exist in the second list. With SQL I would just use "not in" but I do not know the equivalent in Linq. How is that done? So far I have a join, like... var matches = from item1 in list1 joi...
Is there any way to clean up this type of loop using LINQ? List<Car> result; List<string> makes; List<string> models; for (int i = 0; i < makes.Count() && i < models.Count(); i++) { result.Add(new Car() { Make = makes[i], Model = models[i] }); } Basically I'm looking for some way to collate multiple arrays of individu...
I took the plunge this afternoon and began studying LINQ, so far just mucking around with LINQ on collections. One of the first things I tried was to implement QSort. Now -- ignoring the fact that I could just use an ORDERBY and that this is a very silly qsort implementation -- what I came up with was this: public class lqsort { p...
I have a table in the database that I'm retrieving using LINQ to SQL, and as a part of my processing I want to add to this list, then update the database with the new items + any changes I've made. What I thought I could do was this: var list = (from item in db.Table select item).ToList(); [do processing where I modify ite...
I am using link to sql, I have a connected set of objects. I start out and do a linq statement like this Dim L= from II in context.InventoryItems select II Dim L2 = L.tolist The second line was so that I could narrow down where the problem was occuring. When the second line is hit I get an error "The EntitySet is already loaded and t...
Consider this: var query = from r in this._db.Recipes where r.RecipesID == recipeID select new { r.RecipesID, r.RecipesName }; How would i get individual columns in my query object without using a for-loop? Basicly: how do I translate DataTable.Rows[0]["ColumnName"] into Linq syntax? ...
So .NET 3.0/3.5 provides us with lots of new ways to query, sort, and manipulate data, thanks to all the neat functions supplied with LINQ. Sometimes, I need to compare user-defined types that don't have a built-in comparison operator. In many cases, the comparison is really simple -- something like foo1.key ?= foo2.key. Rather than c...