Most voted "c#" questions
This tag should be used when the question refers to some resource, information or problem related to the C#language. C# ("C Sharp") is a multi-paradigm programming language that has strongly typed variables, is imperative, declarative, functional, generic, object-oriented and component-oriented, which are designed to be executed in . NET Framework.
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answer360
viewsHow to get information from a . CPL?
I wanted to make a program that would display all the items on the control panel. For this I need to consult some registry keys, but there are programs that still use cpl files to store the…
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answers14331
viewsHow does Groupby work on LINQ?
I’m having trouble understanding the operator Groupby on LINQ.
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answers3445
viewsHow to create a program in C and use Java/C#GUI?
I’m studying graphic interface in C, and I realized it’s very complex and tiring. So I wanted to know if there is how I create a program in C and use graphical interface of Java or C#. With use of…
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answer1160
viewsWhat’s the difference between Vent and Delegate?
I see how it works delegate and event, but I saw no use of event. For example: public delegate void ChangedEventHandler(object sender, BaseEventArgs e); public ChangedEventHandler Changed; The code…
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answers604
viewsRead all the contents of a text file
I need to read all the contents of a text file and put it into a string. Usually, I do so: using(var reader = new StreamReader("arquivo.txt")) { var strBuilder = new StringBuilder(); while…
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answer3723
viewsMethods Executereader(), Executenonquery() and Executescalar(), what are the differences and how to use them?
I’m working with a database SQL Server in C#, but I noticed that the object SqlCommand has several methods to execute a query, are they: ExecuteReader(), ExecuteNonQuery() and ExecuteScalar(). My…
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answer3531
viewsHow to change the Namespace of a C#project
The project was created with the name Windows and I want to change. The problem is that if I just right-click the project and rename it, the project gets full of error. I tried to change Assembly…
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answers121
viewsIs there an alternative to Removeat()?
I am using Entity Framework in an ASP.NET MVC project where I have a simple list of strings and need to remove only the first item. I used the following command: minhaLista.RemoveAt(0); Well, but…
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answers1063
viewsWhat is the difference between System.Web.Http and System.Web.Mvc?
I have an MVC project and in it I will have normal controls and controls providing services via webservices (Controller and ApiController). And I don’t know which one to use because I don’t know…
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answers1656
viewsCreate objects within a list without for/foreach C#
private List<Compra> CriarCompras(int numComprasParaGerar) { List<Compra> lstCompras = new List<Compra>(); for (int i = 0; i < numComprasParaGerar; i++) lstCompras.Add(new…
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answers2766
viewsCount or Count()
Having a list, what better way to know the number of items on this list and what the difference? if (minhaLista.Count > 0) ; or if (minhaLista.Count() > 0) ;…
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answers309
viewsWhat’s the difference between Savechanges and Submitchanges?
Within the context Entity Framework what is the difference between SaveChanges and SubmitChanges? When I should wear one or the other?
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answer165
viewsLike, when and why use "Securestring" in C#?
I once heard about the class SecureString from C# and it seemed interesting to me, so I think it’s interesting content that can yield good answers from more experienced professionals. Some questions…
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answers359
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answers25519
viewsThe input character string was not in an incorrect format. Operators
Hello, I’m beginner in programming and I’m trying to show the user how much RAM is being consumed at the moment, I’m using the following code that is not pointing nor an error when compiling only…
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answers1625
viewsLambda Groupby by year and month
I have a list of events, and I’d like to group them by year and month, for example [Year 2017] Month January { Event 1, Event 2, Event 2 } Month February { Event 3 } [Year 2018] Month January {…
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answers701
viewsSave and send selected item id in dropdowlinst
I’m trying to do a search, filtering through a dropdowlist. In short, I select a level of instruction in a list and when I click 'Search' I want to return to the list of people who have that level…
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answers17994
viewsWhat is the Difference Between HTML.Actionlink vs Url.Action?
Reading some tutorials of ASP.NET MVC I found these two helpers being used to do basically the same thing, which was to direct the user to a new view. So I wonder if there’s any more remarkable…
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answers4107
viewsConcept of class, entity and objects
I’m reading about classes in C#, and an excerpt left me a little confused. I know that classes are objects in C#, and can be used in various ways. My doubt is in the following sentence: "A class can…
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answer385
viewsIs the C# language recommended to be distributed online with a database?
It is very easy to get the entire code of a C# program using . NET Reflector. Would it be possible for me to put the same security in a C# program a program made in C++? I found that answer no Stack…
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answers1056
viewsHow to make a Split for when there is a letter in the string?
I’d like to make one string be divided with the .Split() every time there was a letter. Example: To string: 97A96D112A109X115T114H122D118Y128 Would become a array with 9 values: { 97 96 112 109 115…
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answers1059
viewsIs it possible to convert a 16-bit number to a single byte?
If I create the following expression: Int16 numero = 2017; byte m = (byte) numero; m will have the value of 225. Okay, how do I get 2017 from the byte m (reverse operation) again?…
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answer259
viewsHow to remove the last number from an integer?
How can I remove the last number from an integer? Ex: int value = 123456789; int newValue = 12345678; Note that the new value does not have 9. I know it would be possible to switch to a string and…
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answers160
viewsHow can I make a string code work with > or <?
Apparently I’m having problems with strings: public partial class Form1 : Form { private int _adicionar; private int _retirar; public Form1() { InitializeComponent(); } private void…
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answers1530
viewsDo programs written in C# depend on the . NET Framework to run?
Once compiled a C# code depends on the . NET Framework installed on the machine to run, similarly to Java?
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answer269
viewsWhat sort algorithm does . NET use by default in a list?
I have a problem that I have to perform sorting in memory of a high number of items and I would like to know which algorithm that the . NET uses to sort when we call the method Sort() from a list,…
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answer578
viewsWhy does iteration of a list with an anonymous object work with an array but not with List<Object>?
I tried the following iteration with C#: var objects = List<Object>{ new {Id = 2, Nome = "Wallace"}, new {Id = 4, Nome = "Cigano"} }; foreach (var user in objects) { Console.WriteLine ("Meu id…
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answer469
viewsWhat is the purpose of empty parentheses in a lambda statement?
I created an example of a Lambda statement with no arguments, however, I have doubts regarding the omission of the empty parenthesis () in the statement. Take the example: class Program { public…
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answer1637
viewsNumber in full for number
I would like to transform an extended number to normal int; example: FunçãoParaConverter("trinta e dois") // retorna 32 FunçãoParaConverter("mil vinte e quatro") // retorna 1024…
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answers283
viewsWhat is the difference between using a comparison with >= or simply >?
Imagine the following scenario. int i = 2; if(i >= 2) { //.... } When we could just summarize to; int i = 2; if(i > 1) { //.... } My doubts with these two expressions are as follows:: When a…
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answer125
viewsApplication C# Windows Forms Slow on certain machines
Good afternoon, I performed the migration of an application that ran in a windows ce to desktop, the Application uses Sql Server Compact 4.0. and runs very well in the development environment, I…
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answers1813
viewsHow to map 1:N (one to many) in Dapper?
I’m using the Dapper which is a micro ORM used to map objects according to the database tables following the relational model. Therefore, I have some doubts regarding the mapping and the structure…
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answers252
viewsDifference between instantiating class and using
I can instantiate a class in two ways in C#, they being: HttpClient http = new HttpClient(); or using (var http = new HttpClient()) { // } Is there any difference between these means? Performance?…
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answers5878
viewsCreating a List<> from a Json C#
I have a doubt regarding JSON, I have the following JSON: { "jsonrpc":"2.0", "result":{ "nr":26, "lista":[ { "codigo":"2", "nome":"Pratos Quentes", "foto":"./images/cupcake.png" }, { "codigo":"3",…
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answers199
viewsWhat are the deconstructors?
When studying about Records in C# 9 was filed the appeal Deconstruct() where the object is assigned to a Tuple. What is a Deconstruct()? Does it remove the reference of the object causing it to…
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answer112
viewsDoes creating local variables all the time generate extra cost for the software?
I made a program of which he writes variables all the time, and with that generated me a doubt, instantiating a variable all the time generates more cost than just assigning the value to an existing…
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answers663
viewsClass generic property
I have a class with two properties (Name and Value). The estate Name is a string, already the property Value I want to leave the variable type. public class Field<TValue> { public string Name…
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answer332
viewsHow to know if path exists?
One of the classes of my system is created with the information of a file. When starting the system, it initially runs the following lines: public List<Estabelecimento>…
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answers3477
viewsPress button with keyboard enter key
I have a record button on my site, I would like to press the "Enter" key on the keyboard this button is triggered, as if it were a mouse click, there is some function to do this? Button code:…
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answers1899
viewsRepetition of if/Else how to reduce and improve code?
I’m starting my programming and a question has arisen during my conditions. I do a check of how many times the result was true, and how many times it was false. Problem is you’re not giving me the…
c#asked 6 years, 1 month ago Pedro Duca 302 -
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answer3160
viewsExcept Print Screen C#
There is a game called Tibia (In same window mode) that when trying to take a print screen the game ends up obscuring the image leaving only the whole black game screen independent if the print…
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answers7413
viewsHow to customize error pages on an ASP.NET MVC system?
How to display a friendlier page when an error occurs in my Asp.net mvc application (not that yellow page)?
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answers2566
viewsIs it recommended to use Linq instead of SQL?
To avoid string abuse and avoid code injection problems can be a good practice using the Linq. I can also imagine, for example, that it’s slower. Who ever used the Linq to communicate with the…
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answers1468
viewsEntity Framework is saving duplicate values when saving entities with relationship N to N
I have an entity called Book that has among other attributes a list of categories. In my model a book can have multiple categories and vice versa, so we have a relationship N to N. EF therefore…
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answers16962
viewsWhat do you call a "Stored Procedure"?
How to call a procedure in ASP.NET C#? Follow my simple procedure: CREATE PROCEDURE GetAdmin ( @email VARCHAR(50), @password VARCHAR (50) ) AS BEGIN SET NOCOUNT ON; SELECT * FROM Admin WHERE Email =…
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answer450
viewsThe parachute descends head down. How do you reverse it?
I made a rocket in Unity that I can take off and land after five seconds. However, it lands that way: I want to get him to the ground with his parachute up. How can I do that by code? Code I have so…
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answers5558
viewsMaster-detail in MVC C# with Razor
Guys I need to set up a master-detail record. I have already researched and seen some examples on the internet, but as I do for when the master is not registered, the details are stored temporarily…
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answers3841
viewsWhy use relics in C#?
What are the advantages and disadvantages of using #regions in the C#? Its use really facilitates code organization? #region /* Código */ #endregion…
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answers7145
viewsIs it good practice to use <Summary> for documentation?
This is the best way to document code in C#? /// <summary> /// Descrição /// </summary>
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answers18905
viewsAlgorithm for betting creation on Lotofácil
One of the ways to bet on Easy Bet is to choose 15 numbers from number 1 to 25. I would like an algorithm in c# that generates bets. Remembering that in each combination the numbers cannot repeat…