Tagged Questions
1
vote
1answer
681 views
Optimising multi-part LINQ to Entities query
I have inherited an application which uses LINQ-to-Entities for ORM and don't have a great deal of exposure to this.
There are many examples like this throughout the application. Could you tell me ...
1
vote
1answer
40 views
9
votes
3answers
654 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
votes
1answer
201 views
Check if Item exists in Grid using Linq
I have a grid which allows a user to enter a new Grid item. If the grid item exists or the tb is empty it displays the error. Here's the code I came up with.
Can ...
4
votes
2answers
349 views
Is this a good way to handle Web API UriTemplates?
I want to be able to do /contacts/Matt%20Phillips and /contacts/1 and have both of them return a contact. The way I did that was ...
1
vote
1answer
30 views
Is there a better way to handle multiple join statements in a linq query?
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 ...
4
votes
1answer
61 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 ...
4
votes
4answers
280 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 ...
8
votes
1answer
78 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:
...
3
votes
1answer
37 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
votes
1answer
51 views
Changing these 2 Function into one function
I have two functions that are similar. The only differences is that their using two different models. How can i change them into one function?
...
4
votes
3answers
1k views
3
votes
2answers
19k views
Faster way to convert DataTable to List of Class
I am using ExcelDataReader to import an excel file to a dataset. Example Excel table below:
...
12
votes
4answers
970 views
Counting the number of points that have both a larger theta and a larger radius than a given point
I don't like the fact that I am selecting all the points, even though I only care about the count of them.
Which of the from parts should appear first, if it even ...
6
votes
3answers
74 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 ...
1
vote
1answer
54 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 ...
10
votes
1answer
275 views
Update first and last item in List<T>
I am trying to do the following. I have a list of Custom objects:
...
4
votes
3answers
158 views
7
votes
5answers
528 views
5
votes
2answers
191 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 ...
4
votes
1answer
150 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
votes
4answers
176 views
7
votes
4answers
334 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 ...
10
votes
2answers
13k views
LINQ to SQL Joining Entities
I have two tables, one for jobs, and one for the names of industries (e.g. automotive, IT, etc).
In SQL I would just do:
...
5
votes
1answer
93 views
6
votes
1answer
129 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 ...
5
votes
1answer
76 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
votes
1answer
130 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 ...
5
votes
2answers
106 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 ...
4
votes
2answers
87 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 ...
5
votes
3answers
229 views
8
votes
4answers
1k views
How to optimize these nested loops for better performance?
I need to optimize this code so it can execute faster, even if that means using more memory:
...
6
votes
3answers
317 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.
...
8
votes
1answer
665 views
Multiple repository calls or LINQ query
These two methods do the exact same thing (or at least they are supposed to!). They both pass a simple test based on a mock context. Neither has been exposed to any integrated testing yet.
Would ...
8
votes
2answers
176 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:
...
6
votes
2answers
346 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
votes
1answer
68 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:
...
2
votes
2answers
330 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 ...
6
votes
4answers
2k views
Sieve of Eratosthenes in C# with LINQ
Can someone look over this Sieve of Eratosthenes implementation? It seems almost too easy.
Rather than maintaining a seperate bit[] to track prime/not prime, I'm ...
3
votes
2answers
210 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 ...
2
votes
2answers
82 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 ...
3
votes
3answers
173 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 ...
12
votes
4answers
959 views
Calculating totals of a transaction
I am working on a project where I have to calculate the totals of a transaction. Unfortunately, coupons have proven to be quite an issue. There are four types of coupons: transaction percentage, ...
6
votes
2answers
698 views
Generic Calculator and Generic Number
.NET does not support generic numbers. It is not possible to enforce a generic method with generic argument T that T is a number. The following code will simply not compile:
...
4
votes
1answer
405 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 ...
3
votes
2answers
93 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
votes
4answers
1k 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 ...
2
votes
2answers
81 views
Add chat to an MVC database: Can I condense this code and is it appropriately placed?
I have these relevant tables in an MVC website:
Server
ServerPlayer
ServerPlayerChat
Servers have serverPlayers, ServerPlayers have ServerPlayerChats. Simple enough and expectable.
I'm using ...
5
votes
2answers
192 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 ...
4
votes
3answers
1k views
VersionString (eg “1.0.2”) IComparer algorithm
For a project I'm working on, I need to compare version strings where:
version strings are composed only of numbers and periods
version strings are made up of an arbitrary number of segments ...
