Language Integrated Query (LINQ) is a Microsoft .NET Framework component that adds native data querying capabilities to .NET languages.

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Producing the intersection of several sequences

Based on this SO answer I have created a method that produce the set intersection of several sequences: ...
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1answer
26 views

Compare / Join two object collections LINQ

I have two csv files that I need to compare and merge together. There is a 'big' list with many records and columns of data and a 'small' list of the desired records and some additional data. The ...
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23 views

LINQ XML Parsing [on hold]

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60 views

Is this the optimal way to write “find these IDs in a list of objects” using linq?

I've got a situation where I have a list of Organizations (code to follow), and a user has a list of OrganizationIds (ints). I ...
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3answers
73 views

Linq query performs poor according to performance analyzer in VS2012

I've a Linq query that performs poorly: ...
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1answer
54 views

LINQ equivalent of nested for loop to select and combine each element from two different lists [closed]

I have two lists defined as such (which represent X and Y points) ...
5
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1answer
72 views

Optimize code block for LINQ and non LINQ

I have 2 code block to do same a work and have same target create some thing, but I don't know which block is the best (I mean LINQ or non-LINQ)? First of all, can anyone tell me how to optimize on ...
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2answers
141 views

Convert a list of sets into the minimum list of non-intersecting sets

I have a list of sets. The same items may appear in multiple sets. I want to transform this into a new list of sets where: Each item only appears once in the entire list of sets. For each set in ...
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1answer
47 views

Improving iterative manipulation on XML elements

In this reply, there's an example of how to remove a node from a XML structure. ...
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1answer
44 views

Dynamic Linq from string with EF

I wrote an EF browser to dynamically navigate through entities. Beside basic properties of system types, each entity can have several singular or plural navigation properties. In order to support all ...
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1answer
48 views

Tasks and WaitAll\WhenAll

Could you help me to speed up/optimize this code: ...
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4answers
90 views

Checking if there are tags or categories in the database

The code below is used to check if there are tags or categories in the database. If they exist, they are not added to the database, otherwise they are added. Is this code efficient and easy to read? ...
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3answers
786 views

Using C# properties for simple operations, where should I draw the line?

Should I be putting Linq statements inside of an objects properties? Is that a best practice or is that a no no? Also if that is ok, where do I draw the line with this? I assume db access is ...
2
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1answer
42 views

Is there a better way to handle multiple join statements in a linq query? [closed]

I am rewriting a VB.NET app into C#. I won't subject you to the original code. I am mainly looking for a better way to handle all the join statements that are being done. I am dealing with a legacy ...
9
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1answer
89 views

Refactor VB.NET to C#.Net using Linq

I am rewriting a VB.NET application in C#. I will not subject you to the original code because it's pretty messy. Below is the converted C# code: ...
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4answers
288 views

A better way to do LINQ projections

I was wondering if there's a better way of doing LINQ projections than what I'm doing below. This method is one of many methods creating a view of an object tree. The first thing that I don't like is ...
3
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1answer
41 views

Updating properties and states

I am rewriting a VB.NET application in C#. This code was originally done in 50 lines and I am trying to clean it up. As you can see I have gotten it down to 10 but I still feel its ugly. I want to ...
3
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1answer
62 views

Changing these two functions into one function

I have two functions that are similar. The only differences is that they're using two different models. How can I change them into one function? ...
5
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1answer
69 views

ListBox Update Handling

I have UserGroups for Users to be assigned to in a ListBox in HTML form. Items from listbox can be multi-selected or completely ...
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3answers
81 views

Searching all diagonals of a 2D M x M array

I've started writing a piece of code to help me search for an object in all the objects found in the diagonals of an M x M 2D array. Though the code works, I'd like to know if there is a way I can ...
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1answer
60 views

Making an email text-parser generic using PredicateBuilder

I have some code that reads an email from a text file, parses the text, removes some lines (the 'cc' and 'to' lines) and then finds the line numbers of various phrases (e.g. "Regards", "Thanks") and ...
3
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1answer
43 views

Optimisation XML handling within vb.net application

I need to optimize this snippet to be faster: ...
10
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1answer
302 views

Update first and last item in List<T>

I am trying to do the following. I have a list of Custom objects: ...
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3answers
196 views

Refactor C# Linq code to reduce duplication

I currently have the below code: ...
5
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1answer
58 views

EF query for calculating monthly trends

My application has a fairly important query that is used in a lot of places. Unfortunately it takes about 14 seconds to run, so I'd like to find a way of possibly improving it. The application ...
4
votes
1answer
157 views

IndexOrDefault that functions like FirstOrDefault

I don't know why this is not in the .NET Library, but I need to be able to use an index against a list and not have it throw an exception if it is outside the bounds of the list. This is what I came ...
6
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4answers
180 views

Simplify LINQ to Create Step Values

Assume the following definition: ...
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4answers
340 views

File text searcher

I have a working version of a logfile searcher that targets a specific directory by extension type, and searches the files for certain words. I'm wondering if my method is the most efficient ...
5
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1answer
99 views

Nested LINQ Nightmare, calculating %completed

This code horrifies and scares me. I wrote this. ...
5
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1answer
83 views

Combining List<>.ForEach and List<>.Zip

I have three lists, and I need to operate on the ith element of each list simultaneously. ...
4
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1answer
262 views

Convert hex string to byte array

The goal is to convert a hex string to a byte array with the following requirements: \$O(1)\$ additional space apart from input and output. \$O(n)\$ runtime This mostly just prohibits creating a ...
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2answers
228 views

Efficient way to get every unique combination of “Pick 1 number from each Group of Numbers”

My question is: Using C# and/or Linq, how can this existing code be improved to be more efficient? (My "Complex" example takes about 5 seconds to run, how to make it faster?) What the code is ...
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2answers
144 views

Adding object to database, using linq or sql connection

I have a table called tblDelegates in my database which I need to populate with some data. I have created a class called Delegates which has various properties to ...
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2answers
95 views

Create a LINQ Killer Sudoku Cage Solver

When playing Killer Sudoku I find myself repeatedly writing stuff like this: 12/3 921 831 741 732 651 642 543 and then crossing out the combinations that include ...
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1answer
137 views

Refactoring a LINQ query that (sometimes) returns null

I have the following LINQ query that should return a result for each Request. I'd prefer to have the query translated to ...
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3answers
434 views

Get distinct combinations of numbers

The below code returns all distinct combinations based on the logic that 1,2,3 = 3,2,1 = 2,3,1, so it only returns 1 instance of that set of numbers. ...
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2answers
183 views

Take previous element from array if condition on current element matches

Any ideas to simplify this beauty; I would prefer a LinQ expression if possible: ...
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2answers
592 views

Web service getting value using LINQ from queue table in SQL database

As a test of my C# skills, I have been asked to create a simple web service which will take a message from a queue table in a SQL database and send it to a web application when a button is pressed on ...
2
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1answer
69 views

Is there a better way to do this linq sort?

I have the following linq statement that is ordering a list of assets by the sort order of a child item: ...
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2answers
542 views

Sum(), ForEach() with Lambda in a hierarchical List Collection

I have to list the number of documents related to items in a hierarchical tree. The specification states: The tree will only ever be 2 levels deep. The higher level items will list not only the ...
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2answers
226 views

Extracting Pixels From Image Byte[]

I have a requirement where I need to extract pixels of a given rectangle within an image byte[]. More specifically I have an image where I have narrowed an area ...
3
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3answers
226 views

Test questions - Number Generator, Linq, Delegates, Sequences

I have recently been asked to do a test prior to an interview to test my C# skills. I am fairly new to C# (6 months) and I think this showed with me producing an overly complex answer to their ...
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2answers
89 views

Mixing Linq queries and Linq lambdas

I have been given a change to rewrite an old framework we use, and to implement the repository and unit of work patterns, but in an attempt to not rewriting all queries I have ended up with a weird ...
4
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1answer
412 views

Linq queries performance

I am fetching data from the database using entity framework and linq queries. I am wondering about the performance of getting data. Here is my code. I just want to check that a Well exists in ...
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2answers
102 views

Copy two properties from one array item to matching index in another array

I have two IEnumerable objects called items and newItems. I need to update the Did and ...
8
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4answers
2k views

Single line FizzBuzz solution in LINQ

Now FizzBuzz itself isn't a big challenge but I agree that it can be a good tool to see if someone can code or not. I wanted to practice my LINQ a little bit so here's my single line FizzBuzz ...
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2answers
159 views

Check database for item and create it if it doesn't exist

Is there a more efficient approach to this code? ...
2
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1answer
70 views

Compare Collection with the information in DB using EF and LINQ

I want to inform the Receivers about new contracts we have this week. After I sent the Emails, the Information about sent contracts are stored in MS SQL Database. To avoid that someone become the ...
4
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1answer
165 views

EntityFramework-based filtering

I am trying to use the following form to enter new info into a database. I am trying to use the entity framework. I have the following classes of Interest: ...
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2answers
200 views

Getting list of daily team goals

The old code I had before was atrociously slow but after some advice and research I was able to take a 2-5 minutes run time down to about 5-30 seconds. That is acceptable, but still looking to have ...