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5
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answer645
viewsMask for formatting Textbox
I was practicing coding on a project like Winforms, A question soon arose: How to apply a phone mask on a Textbox. So the first thing that popped into my head was to use the event Keypress of the…
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answer322
viewsConcatenate columns into rows
I’m trying to take several columns and turn them into a single row, but without success. That’s the select I’m trying to make: SELECT (`dias2produto`+`dias4produto`) as 'Até 4 dias',…
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answer205
viewsWhat is the size limit of Indexeddb technology?
Today at work they mentioned the technology IndexedDB to solve a problem here in the company, but Between several questions arose me, being one of them: What is the data limit that can be stored in…
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answers96
viewsConvert a list with different line dataframes into independent dataframes
I have a list with 3 dataframes, which derive from the function split: > split $`1` bin group1 group2 missing score1 score2 gender size score3 income city 0 1 1 NA 3 2 M S 4 1605.525 San…
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answers25119
viewsHow to discard all commited changes?
How to discard all commited changes? Example: I have a project that has a few dozen commits, assuming that at a given moment I decide to discard everything which has not yet been confirmed via…
gitasked 6 years, 2 months ago Fábio Jânio 3,407 -
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answers64
viewsIs expression-bodied recommended? Is there a performance difference?
The extent to which it is recommended, or even good practice to use Expression-bodied? I know that the Expression-bodied allow properties, methods, operators and other function members to have…
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answers109
viewsHow to return to the previous state? (Vuex)
I am using Vuex to manage the states of my app and I am creating a forward button and a back, in case of my advance I use the function below: addUser() { const payload = { name: this.name, email:…
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answer101
viewsPersist data in related tables (1 x N)
I have these 2 related classes, and the requested class has a Collection of "Itenspedidos"... The Request class: public class PedidoDTO { public int pedidoID { get; set; } public int codigo { get;…
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answers651
viewsHow to perform the tapply function for multiple dataframes in R?
I wish to perform only ONE function tapply and get results for each of the dataframes at once: dataset1<-data.frame(group = rep(c('a','b','c','d'), 3, each = 3), number1 = c(1:36), number2 =…
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answer950
viewsHow to put a <div> inside an iframe?
So, I’m trying to get only one part of my HTML page updated, every "X" time. I was trying to accomplish this through AJAX, but it was giving many problems. So I decided to change the plan. This is…
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answers239
viewsGET request is not answered correctly by backend
The project is an Angular 6 front-end, which connects to a Java back-end for communication with a SQL Server BD. The server that receives the file .war, containing both the back and the front, is…
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answer478
viewsHow to find out which path is followed by a function in js
Explaining my scenario, using emberjs, and it encapsulates each Component within a Controller that will be encapsulated inside a Router, and still has a scheme of Model, Mixins, Helpers, when there…
javascriptasked 6 years, 2 months ago MarceloBoni 6,385 -
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answers1042
viewsHow to create a Datatable that has a dynamic column structure?
Hello, I need to create a Datatable in my MVC project that will not have predefined columns. The amount of columns should be defined from the amount of data existing in a BD field. I have a field in…
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answer1426
viewsWhat is the . isidentifier() method used in Python?
I came across the method string .isidentifier() and also the .isprintable(). Why use them? On what occasions would I wear this?
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answers283
viewsCreate list with more than one element as if it were multidimensional
I need to receive these pairs of data from the bank, and I’m thinking of a way to bring the values without creating an object, because I think it’s unnecessary in this case. It is possible to create…
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answers718
viewsAssign values to arrays
I realized that by increasing a value to one array using the following syntax: let array = []; array['nomeIndice'] = 10; the length that array is not incremented, and continues in 0, despite the…
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answer98
viewsDoubt when designing a database
What is the best way to design a database for a web system, for example, this system is for doctors, and every doctor has his or her schedule, patients, cashier, etc. What would be better: A single…
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answers465
viewsHow do I verify registration in real time?
I have a registration system that I need to check in real time if the email exists in the database. But the same is not working, in the <div id="resposta"></div> does not display any…
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answers140
viewsHow to verify if a type is numerical in C++?
Let’s assume I have a function: template<class T> T soma(const T& x, const T& y) { static_assert(/*O tipo é for numérico?*/, "Tipo de argumento inválido, O argumento precisa ser…
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answer722
viewsGoogle Maps, doubt about overlapping radius of markers
I implemented the Google Maps v3 API in Javascript in a reservation system, in the system I used PHP to connect to the Mysql database to return the units of a franchisor that already exist and are…
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answers4418
viewsError in a simple SELECT with Group By - SQL Server
I’m trying to do the following SELECT: SELECT P.Nome,P.TipoId,P.QuantidadeMensal FROM StockPhotos.Pacote P GROUP BY P.QuantidadeMensal; But I’m getting this error message: Message 8120, Level 16,…
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answers10051
viewsHow to change the background of a CSS-only checkbox?
CSS in width and heigth has an effect, because background-color nay? input{ width: 20px; height: 20px; } input:checked{ background-color: blue; width: 25px; height: 25px; } <input…
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answer34
viewsHow to provide module configuration correctly?
I’m creating a module of Node.js and wanted to provide usage settings. Let’s say I wanted to provide a prefix for the console.log just as an example: let opcoes = {}; function imprimir(texto) {…
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answer1890
viewsDatetime.Now or Datetime.Utcnow
What’s the difference between DateTime.Now and DateTime.UtcNow ? DateTime dateNow = DateTime.Now; // retorna {01/08/2018 18:28:15} DateTime dateUtfNow = DateTime.UtcNow; // retorna {01/08/2018…
c#asked 6 years, 2 months ago Matheus Miranda 5,375 -
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answer439
viewsDo I need a macOS computer to program Swift 4 and Objc?
I’m doing a lot of research on iOS app programming, and all the online courses I find on the computers are Apple-based. To program Apple, you need an Apple computer?
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answers820
viewsGET, POST or PUT, which one to use to issue a invoice?
Which should I use when the intention is not to view, save or update the data? I’m creating an API that makes the issuance of an electronic invoice, I made the complete CRUD for the information of…
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answer663
viewsViews do not recognize @model, @Viewbag, @Viewdata
I am using Mono 5.10.1 and Visual Studio Professional for Mac (Version 7.5.4 build 3) Views do not recognize tags like @model, @Viewbag and @Viewdata, either in older projects that were originally…
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answers555
viewsCreate an "opacity" on top of a <tr>
I have a dynamically generated table: I would like to create a class in CSS to make a "layer" on top, with transparency. Example: If I use the background-color, it will only change the background,…
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answer873
viewsHow to display dates set in datepicker only
I’m wearing a lib calling for Multidatespicker similar to the DatePicker of JqueryUI. Currently in the panel I can select the dates I want, works normally, but the same calendar is displayed for the…
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answer167
viewsMemory overflow with mysqli_query
The following instruction stopped the program: $result = mysqli_query($db, 'SELECT * FROM base'); And returned the following error: PHP Fatal error: Allowed memory size of 134217728 bytes exhausted…
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answer371
viewsSecond backslash in metacharacters when the expression is in quotes
When using a pattern between quotation marks a second backslash must be added (\) in the meta-characters that have such a bar, as in this case, for example: /\d+/ -> "\\d+" Code examples: var str…
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answers190
viewsCSS catch siblings before element?
Well basically, I have the following structure, where when the hover is activated in an element, the brothers on the right must receive an exclusive style, while those on the left must receive…
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answers104
viewsCommunication of c# and c++
How can I make the C# code call a variable that is in a C++ file for example. Knowing that I am using Visual Studio. Code C++: #include "stdafx.h" #include <iostream> int main() { int test =…
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answer817
viewsDarken background by hovering the mouse on the link
Hello, How to make a darkening effect on the bottom of the site by hovering the mouse over the main title? Like this site: https://www.santander.com.br/ I tried this addClass but it didn’t work :(…
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answers172
viewsSQL SERVER - Convert String in Days
How can I convert this string in days? Example: return "2 days and 2 hrs"? SELECT '50:00:00'
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answers1448
viewsConverting word file to pdf
There is a free library that I can convert word file to pdf ? I have word file saved database with type varbinary(MAX) and I recover as byte[] in C# and I want to convert word to pdf to show on HTML…
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answers293
viewsUniquely identify the smartphone
I have an app that needs to uniquely identify a device. Even if the user removes and installs the app again, I would like the handle to continue the same. At first, I thought about using the…
androidasked 6 years, 3 months ago Thiago Luiz Domacoski 7,310 -
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answers1346
viewsDifference between ADO.NET and Dapper
What are the differences between Orms? When to use one and when to use the other? What are the disadvantages of each?
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answers482
viewsRescue only 10 first Python object records
I am wrapped in a piece of code that I am doing. I need to rescue only the first 10 records of an object that I call into a for loop: listaTabela = [] for aluno in alunos: listaLinha = "" listaLinha…
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answers7405
viewsWhat is the difference between SCHEMA and DATABASE?
I had never used Mysql Workbench and it instead of database, gives me the option of SCHEMA. What is the difference between the two? It gives in the same one or the other?
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answer187
viewsInclude HTML in HTML without affecting SEO
I’ve seen a lot of ways to include a file HTML within another HTML, so much for Javascript as by the tag <object> of HTML5. These include types negatively affect page SEO? Content included in…
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answer425
viewsWhat is the Pumping Lemma (or Pumping Lemma) ? And how to apply it?
I was reading by HOPCROFT and had difficulty applying the pumping lemma in a formal way to exercises to prove that a language is not regular. In this case, I refer to the Pumping Motto for regular…
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answer121
viewsWhat is the uneval function for?
I was seeing some things in Javascript (which seems new to me) and I came across an example that showed a function called uneval. Some questions below about her: This function is new in Javascript…
javascriptasked 6 years, 3 months ago Wallace Maxters 102,340 -
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answer647
viewsHow to deal with multiple quotes in R?
My problem is using quotes in a query within a R function. I have to call a list of select * from probes."probes_90_2018-05" For that I do: coelho<-dbConnect("PostgreSQL", fnord)…
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answers129
viewsWhy are Javascript objects not always JSON?
For example: { "nome": "Meu nome", "sobrenome": "Meu sobrenome" } Can it be considered an Object and also a Json? If not, why not? What will differentiate one from the other is when instantiating?…
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answers240
viewsSpecialization and generalization in databases and application development
I have a table Livros and I know that the specialization/generalization of books are Livros de Ficção, Livros de Drama and Livros de Suspense, for example. However, in the logical model, I don’t…
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answers3690
viewsRegex to capture words between two characters
My problem is this: let texto = "teste :1: e também teste :2:" What I need to do is basically take the positions where these characters appear :1: and :2: with regex, since what appears between the…
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answers960
viewsHow to make a Scheduledexecutorservice launch a new task while the previous one has not yet finished?
I am implementing a Scheduler to run some threads on my system at x time intervals. The big problem is that if thread 1 has not yet finished running, 2 does not start, even though its time has come.…
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answer261
viewsCSS: Border Radius
I’m doing a project where I’m using the border radius to make a vertical menu. I would like the Menu to have the border Radius straight, this rounded shape : And it’s actually getting this way:…
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answer2777
viewsPython file comparison program
Personal I am with a doubt and a great difficulty to create a program that reads 2 files, example doc1.txt and doc2.txt, within the files has the following data: doc1.txt doc2.txt 1 1 1 2 2 5 3 6 4…