i'm using Asp.net MVC with Sharp Architecture.
I have this code:
return _repositoryKeyWord.FindAll(x => x.Category.Id == idCAtegory)
.Take(50).ToList();
How can i order by random?
Note: i don't want to order the 50 extracted items, i want order before and then extract 50 items.
Now I know there is a reason to this odering but my tiny little brain can't get my head around it.I am using a webservice to pull through data to a webp[age and have the following that is so far pulling data through from UUF1:
public string[] GetBuyer(string Memberkey)
{
try
[code]...
I have a pretty complex Linq statement with multiple joins, but am having a problem with an orderby statement.
I think I can reduce the question down a bit, but will expand if needed.
First my object has the following properties:
myObject.ID This is a basic Int
myObject.BrandName This is my HashSet<string>.
I need to sort my Object by the BrandName using the lowest or highest value depending on if I am sorting ascending or descending.
Is there a way to use the OrderBy command in Linq with a DateTime field using the Date portion only (without the Time Stamp portion) that is nullable such as in the following query?
var query1 = from myTable in MyTable
where myTable.EnteredDate != null
group myTable by myTable.EnteredDate into myOutput[code]....
Since myTable.EnteredDate is a DateTime field that can contain nulls, it does not support the .Date conversion call such as
myTable.EnteredDate.Date
Is there a way to convert the myTable.EnteredDate field into a date only string in the group by portion?
I am trying to get my head around the sharp architecture and used the visual studio template as described on the web:[URL] This is all cool. Unfortunately, I cannot add a strongly typed view as easily as I am used to 'under' asp.net mvc.
What can I do to 'enable' this in VS 2008 Prof? I have also installed asp.net mvc 2.0 and would like to reflect this in my 'vs studio sharp environment'.
I'm trying to follow the demo from this link to add a jqGrid to an MVC app.
I have a table named Companies that I'm trying to display in a grid. A Company simply contains an ID and a Name.
I'm running into an error in my controller function:
public JsonResult DynamicGridData(string sortIndex, string sortOrder, int page, int rows)
{
int pageIndex = Convert.ToInt32(page) - 1;
int pageSize = rows;
var companies = companiesRepository.Companies.OrderBy(sortIndex + " " + sortOrder).Skip(pageIndex * pageSize).Take(pageSize);
//Error here
...
}
I'm getting an error on the line that is calling OrderBy():
The type arguments for method 'System.Linq.Enumerable.OrderBy(System.Collections.Generic.IEnumerable, System.Func)' cannot be inferred from the usage. Try specifying the type arguments explicitly.
I really have no idea what the error means, and I haven't been able to find an explanation. I'm not sure what is causing this error on a simple OrderBy function.
I've build a linq query.But i want a random selection so its not always ID : 1,2,3,4,5,6 How can i randomize this var? I like to bind it to a repeater.//TagCloud:
Random rand = new Random();
var tc1 = from i in JumpTide.cms.menu.GetMenuItems(32)
select new
[code]...
how to pull a RANDOM item from the database when using LINQ. There seems to be a couple of differnet ways to handle this. What I need to do though is pull a RANDOM item from the database that the user has not seen before.
The data I am pulling from the database is very small. Is there any way I can just hit the database once for 1000 records and then randomly scroll through those?
Should I put a cookie on the users system recording the IDs of which items they have seen, pull a random record, check to see if it is seen and if so, pull from the database again? That seems like performance issues just waiting to happen.
I have this LINQ query:
var agnts = (from a in db.agents select new { a.userid, a.name }).Take(10);
How can I get randomly get 10 records from my agents table?
I have tried:
agnts = agnts.OrderBy(n => Guid.NewGuid());
but this doesn't seem to do anything.
I am creating an Asp.net web site which will support dynamic data. When I am creating a dynamic web site from Scratch (from template in VS) all is working fine. But when I am trying to add dynamic entity (.edmx) file and running the application I am getting following error
"The method 'Skip' is only supported for sorted input in LINQ to Entities. The method 'OrderBy' must be called before the method 'Skip'. "
We say that "GroupBy" and "OrderBy" methods from LINQ as Extension Methods.Then how about "variable.ToString()" and "string.Split()" menthods. Are these Extension methods.
View 2 RepliesI want to use Linq to SQL in my web projects. I mostly work in small and medium size projects. Please guide me what layers I should use ?
Previously I was using DAAB and was using 4 layers (business objects, business logic layer, data access layer and user interface).
We have a web solution. In it we have 2 websites and a core project in the core project are some classes that encapsulate data that a database utility class searches using sql and populates the entities. The entities are stored in generic lists.
We have just upgraded our project and I want to start using linq, I was wondering the best way to go about it. SHould I creata new linq project? Or Should I just use ling on new pages only and stick to our current data access layer for pags that already exist?
Its vital that we start using linq as it will save us time in the future
I need some guidance for an application I am working on. I have searched the web and the forum and found parts that answer my questions but I want to do this correctly. My solution uses LINQ to SQL to model the db and I have a repository that is querying my db everytime a controller needs to get some data for the view. I am initially anticipating a maximum of only about a few hundreds hits per day (if that). The website is a directory, with listings and requires a search functionality.
1. What options should I consider to avoid having my repository query the db everytime
2. The site contains a 'search' option, how can I implement this against my repository?
I guess I'm really looking for someone to point me in the right direction. So far I've looked at 'caching' the LINQ to SQL model and Lucene.NET but both seem overkill or am I missing the point?
i build online course selection for a university now i want to make it layering and i dont know to make it 2 layer or 3 layer i mean mix business layer and database layer because i use linq so it is not require to check request data that in sql from client in business layer because linq check it autimatically to preent injection and etc.is it right?can i put my class and DB class in same place or layer?if i make it 2 layer the performance becom better?
View 5 RepliesI create a table as picture below :
when I insert any character to column Name then A new string random will auto insert into column Random (picture below) I had used Trigger but It was error !
I want to column Random use to code :
DECLARE @myid uniqueidentifier
SET @myid = NEWID()
insert into table_1 values(@myid, substring(CONVERT(varchar(255), @myid), 1, 5))
but It must auto like column Number (column Number is Identity)
I am updating a project I wrote some time ago. At the time my preference was for DataSets and DataSetTableAdapters, but I've now moved on to use Linq to SQL DataClasses. I would like to convert the project to Linq to SQL, but I am tight on time and it's a big job. My question is, is there any reasons I can't develop new modules using Linq to SQL DataClasses along side DataSets and convert the DataSets overtime?
Apart from the obvious confusion it will cause, are there any technical problems I should be aware of i.e. will there be any performance problems using the two methods?
I have installed Framework 4 and I declare a structure:
[Code]....
Then I use it like this:
[Code]....
On my pc everything is fine, but when I move my file to a server hosting with Framework 3.5, I get the following error:
error BC30456: 'OrderBy' is not a member of 'System.Array'.
I'm very new to the whole thing and am slowly building a little app which takes a series of numbers into an array,orders them,does calculations and outputs the result.To this end I'm using arrays declared like:
string[] and the function OrderBy().
Eventually this little prog is intended to read text files containing perhaps thousands of values so I thought I should find out:
What are the size limits for such arrays?What are the size limits for OrderBy() ?
Is OrderBy() an effective sort routine for large arrays or does it get very slow?
I hope it is okay to ask these questions.I realise I could find out for myself as soon as I've got it to where it can upload and read a text file and process it...... but I'm not there yet.
I'm playing with an EntityDataSource and specifying a simple order by clause containing one column name, for instance "it.[DNS_NAME]".
When I run the following:
[Code]....
I get an EntitySqlException saying that @sort's type is incorrect. It is expecting a Transient.rowtype that matches one of the columns. What is going on here? Order by parameters don't really have a meaningful type other than a string in my opinion. When I try specifying DbType.String instead of TypeCode.String, the same error is thrown.
The exception:
'@sort' is not a member of type 'Transient.rowtype[(SOFTWARE_DSPL_ID,Edm.Int32(Nullable=True,DefaultValue=)),(COMPUTER_NAME,Edm.String(Nullable=True,DefaultValue=,MaxLength=64,Unicode=True,FixedLength=False)),(DNS_NAME,Edm.String(Nullable=True,DefaultValue=,MaxLength=64,Unicode=True,FixedLength=False)),(DIRECTORATE_NAME,Edm.String(Nullable=True,DefaultValue=,MaxLength=24,Unicode=True,FixedLength=False)),(OS_BROAD_CAT_NAM,Edm.String(Nullable=True,DefaultValue=,MaxLength=25,Unicode=True,FixedLength=False)),(OS,Edm.String(Nullable=True,DefaultValue=,MaxLength=64,Unicode=True,FixedLength=False)),(EQP_TYPE,Edm.String(Nullable=True,DefaultValue=,MaxLength=64,Unicode=True,FixedLength=False)),(EQP_PROP_NO,Edm.String(Nullable=True,DefaultValue=,MaxLength=10,Unicode=True,FixedLength=False))]'
in the currently loaded schemas.
How can I dynamically provide the column name to order by?
I'm currently trying to work out the best way to build this web application, which will then be intergrated on other systems, such as WinForms, Intranets etc.
We hope to include the usual layers i.e. DAL, BLL, BOL and UI but I have been experimenting with Entity Framework 4 and WCF Data Services and managed to get something in place where I was using WCF as a gateway to EF4.
i.e. Adding a Service Reference to my project and then using the EF4 context and writing LINQ queries against the DB
e.g.[Code]....
Now with the current setup I would still need to write a DAL Class Library, that interacts with the Data Service, because as I said WCF Data Services only seems to be a gateway, I can't see where to put the code (above) in the Data Service and then how I could these methods.
My questions are: 1. How do I develop a WCF Data Service in such a way to allow this behaviour - I know how I could do it using ASMX web service, something like [Code]....
2. If I am to use WCF Data Services, how is serialization handled (if at all) - again I know how to do something in ASMX web services
3. Again, If I am to use WCF, how do I add Security and only allow my applications to access the web service - for obvious reasons
4. Would it be possible / logical to also include the Business Logic Layer into the web service?
which is the better language in terms of coding, proficieny if we compare between VB.Net and C Sharp.
View 7 RepliesWhat does the underscore mean in C Sharp?
I saw a program,
Csharp Code:
Class Metals {string _metalType;public Metals(string type){_metalType = type;Console.WriteLine("Metal: " + _metalType);}}
What does the _ (underscore) mean in it?
Does that mean any static variable or something else?
I am unable to show message using msgbox.show method in c sharp which we can use in Vb.net.
How to implement such thing in c sharp
What is partial class in c sharp and whats the use of it, how to implement the partial class
View 6 Replies
