MVC2 LINQ - Repository Pattern, Where Should The Pagination Code Go
Nov 2, 2010
I'm working on adding an HtmlHelper for pagination, but I am unsure where the proper and/or most beneficial place to put certain parts of the pagination code from a performance and maintainability standpoint.
I am unsure if the Skip(), Take() and Count() portions of Linq to SQL data manipulation should live within the repository or the controller.
I am also unsure if their order and where they are used affects performance in any way.
If they live within the repository from my understanding this is how it would work:
1. I would pass the pageIndex and pageSize as arguments to the repository's method that grabs the data from the database.
2. Then grab the full data set from the database.
3. Then store the count of TotalItems of that full data set in a variable.
4. Then apply the Skip() and Take() so the data set retains only the page I need.
5. Display the partial data set as a single page in the view.
If they live in the controller from my understanding this is how it would work:
1. I would grab the full data set from the repository and store it into a variable inside of the controller.
2. Then get the count of TotalItems for the full data set.
3. Then apply the Skip() and Take() so the data set retains only the page I need.
4. Display the partial data set as a single page in the view.
Inside the controller (I realize I will incorrectly get the page count here and not TotalItems):
[code]....
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Oct 13, 2010
We have an ASP.NET MVC site that uses Entity Framework abstractions with Repository and UnitOfWork patterns. What I'm wondering is how others have implemented navigation of complex object graphs with these patterns. Let me give an example from one of our controllers:
[code]....
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[Code]....
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Mar 8, 2011
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Jul 8, 2010
This is possibly the worst kind of religious debate -- a religious debate with practical consequences. But it's one that needs to be had, and I can't seem to fit it in my tiny head. Here are the pros and cons of the pattern as I know them:
Pros:
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-Facilitates unit testing by allowing itself to be abstracted into an interface
-Creates an opportunity for business-level validation
Cons:
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Dec 21, 2010
I am currently using the 3-tier Repository pattern in my application. Actually it's the first time for me to implement a design pattern at all! i used to put all my code in the so called now presentation layer.
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[Code]....
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Jan 17, 2011
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I am trying to understand the fundamental differences between the Provider Model and Repository Pattern.
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Mar 4, 2010
I'm used to working directly with SQL and do NOT want to use Linq.
Pretty much I always create a class like the one below and have all the functions/methods necessary to perform a task.
How would I set up a repository without using LINQ??
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.Sql;
[Code]....
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Apr 15, 2010
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All paths seem to lead to a huge constructor which manually sets the values of each individual property. But I never had to do that before when I wasn't using a ViewModel. Model binding was a blessing! My objects also have complex child objects, which my form is also collecting values for, so this would be a huge/verbose task against DRY principals. I don't even really want to use a ViewModel, but am forced to because I need two different DataAnnotations rule sets for different validation scenarios applied to the same object.
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