Posts by Maniero • 444,682 points
6,921 posts
-
7
votes5
answers146
viewsA: Is there a disadvantage or is it harmful to use null types?
Yes, whenever the null is not part of your domain, which is rare to occur. So bad that in C# 8 the reference types that were null by default cease to exist (If you turn this on, it can’t be…
-
1
votes1
answer647
viewsA: Dynamic allocation in C++
If you were learning to allocate memory like that on the Internet, just run. Almost all the content on the internet about programming is bad, something saved and for a layman it is very difficult to…
-
4
votes2
answers211
viewsA: Why is it wrong when I try to assign a value to the variable within a conditional operator?
You can do what you want, only the syntax was a little wrong, see that it can be even simpler: #include <stdio.h> int max_of_four(int x, int z, int y, int w) { int max1 = x > z ? x : z; int…
-
3
votes1
answer55
viewsA: When to use "rsize_t" instead of "size_t"?
Basically it’s a semantic question, you get a better idea of what you’re doing. So it says you’re choosing a size within a certain range. In fact it seems that they consider it useless and there is…
-
5
votes1
answer88
viewsA: Can you store a throw in a variable?
The throw can’t because he’s a statement and not an object, but the exception can yes, because it could not? It is an object like any other, as is a text or a numerical value. Again I come to say…
-
1
votes1
answer379
viewsA: What are the differences and advantages between "typedef struct" and "struct"?
In C++ there is no important difference (there are some corner cases but don’t worry about it), all struct is typedefed automatically (at least if I’m not inside a function, I don’t remember if the…
-
11
votes1
answer2211
viewsA: Is there a module function of a number in C#?
For me module in programming has always been what this operator does, so the rest of the description is contradictory, but what you described seems to be that you want to take the value without…
-
1
votes1
answer111
viewsA: What is the difference between the constructor method and the use of setters in Javascript object orientation?
About the builder has already been answered in: What good is a builder?. In general it is a mistake to work only with getters/setters precisely from what is written in link above, but for everything…
-
1
votes1
answer66
viewsA: Put date 5 days in advance
Just what you want? let meses = ["janeiro", "fevereiro", "março", "abril", "maio", "junho", "julho", "agosto", "setembro", "outubro", "novembro", "dezembro"]; let data = new Date();…
-
6
votes3
answers290
viewsA: How to make compatible objects coming from two different classes, derived from the same interface?
There’s at least two problems there. Double definitions of the same object One of them is to have two Cliente being the same object. This definition should be canonical, this will cause several…
-
2
votes1
answer2470
viewsA: What is the difference between PWA and TWA (Trusted Web Activities)?
The main point of a TWA is to actually be available in the Play Store (as an APK) and so it needs to conform to its rules, on the other hand it gains some rights (minimum) that before could not with…
-
8
votes2
answers278
viewsA: Matrix or Vector, huh?
It has no advantage if you don’t need the matrix. It is not a question of having one advantage over the other, these two types of data are not comparable, they are for different needs. So to say…
-
2
votes1
answer418
viewsA: How to reverse the order of a String in Dart?
Since you are looking for a ready-made way (not the most efficient way): void main() { print("teste".split('').reversed.join()); } Behold working in the ideone. And in the repl it.. Also put on the…
-
0
votes1
answer384
viewsA: There is no mapping of the System.Windows.Forms.Toolstriptextbox object type to a native type managed provider
You have to take the value of the GUI object for a simple object, you can’t be sure because you don’t have enough information on the question. It can be: toolStripTXT_Pesq_Cnpj.Text I put in the…
-
2
votes1
answer61
viewsA: Does class commentary slow the eclipse?
I will not state categorically, but it does not cause anything very significant, at least it should be something very small and imperceptible. I know Eclipse does a lot of analysis while you’re…
-
6
votes2
answers223
viewsA: Are parameters with vectors in Java always by reference?
I am aware that, in Java, any parameter passage of an object is by reference Your science is wrong, only objects originating from classes are passed by reference. Objects coming from other forms are…
-
2
votes1
answer74
viewsA: Calling recursive function with decreasing operator
Why use this operator there? What do you expect to get out of it? It will decrement a variable that will not be used later, so it makes no sense to do this, it’s only making the code inefficient and…
-
0
votes1
answer85
viewsA: How to return a number as if it were a date?
Except for the fact that the function is too complex, the only problem is that it has a double quotation mark right there after the two single quotation marks placed as separator for the join().…
-
3
votes1
answer48
viewsA: Handling object only in methods
Classes are data structures, they serve only to declare what must be in this structure, it cannot have algorithms (have it done), the place of algorithms is the method. Classes do not guarantee…
-
10
votes1
answer170
viewsA: Would it be bad practice to insert monetary symbols directly into the bank?
This question is the opposite of: CPF or CNPJ field type in VARCHAR or INT database?. In that person wanted to put descriptive data as if they were quantity and was wrong. Now this question wants to…
-
3
votes2
answers110
viewsA: Mount "if"s according to criteria
Probably has a conceptual error in the system, but since it is so can solve this way (I hope I understood and have been correctly put the criteria): <?php if($transaction->status ==…
-
3
votes1
answer147
viewsA: Injection of dependencies into functions and not classes. Is it "wrong"?
For me the way you want to do it is dependency injection done right. What I don’t like is strutting to do something simple. Creating parameter in function or field in class with the sole purpose of…
-
4
votes3
answers1332
viewsA: Format DATETIME SQL Server
Data does not have formats, date is date, has a point in the timeline, only that, formats can be applied in texts that are visual representations for humans to read dates (the same goes for…
-
2
votes1
answer92
viewsA: List private properties
Is there any method that lists private properties? The simplest way is with get_object_vars(). If you want to filter the toilets you can use reflection: new…
-
4
votes4
answers712
viewsA: How to access only the first position of each row in an array of arrays (matrix / multidimensional array) using foreach?
You have to manually pick up the first column and so can not use the foreach, for that exists the forgross and the method GetLength() which gives the size of a dimension, how you want to walk in…
-
4
votes1
answer273
viewsA: How to assign a character to a string position?
I think that’s what you want (simple, right?). I didn’t want to change too much and I kept your logic (I think it can be improved). I changed the pointer to reference which is the most correct in…
-
3
votes2
answers87
viewsA: String scanf() time problem
It makes no sense to read this way, ask for a whole and be happy. Understand that these standard C console mechanisms, especially reading, exist only to do very basic things and in real code people…
-
5
votes2
answers132
viewsA: How to correctly read documentation from an SQL command?
Keys are a form of grouping, meaning that everything in there is one thing, it’s like parentheses in a normal programming expression that eliminates ambiguity. So obviously inside has more than one…
-
0
votes1
answer43
viewsA: How to use a function to check the requirements imposed on a variable in C++?
The solution when something doesn’t work is to investigate what is wrong, to learn how it is right, not to complicate more and cause more mistakes. Your code has too many things, it’s not about…
-
1
votes1
answer70
viewsA: Sum does not present the expected result
The result of your code already hints at the error. It says that "the sum of 4 and 4 equals 8", so you are not reading your screen. Then it is clear that you are taking the same number, the first…
-
0
votes1
answer38
views -
2
votes2
answers82
viewsA: Add decimal values in Mysql
Column names should be written directly, not in quotes, so you’re having a text add up, which doesn’t make any sense. Then the right thing would be: SELECT SUM(ValorTotal) AS Pagos, StatusCadastros…
-
2
votes2
answers70
viewsA: Is it better to use overloading or add an "if" with the optional parameter?
It depends, as always. in most cases the simplest. For this case it seems to me that the first case is better because it is simpler, I always prefer the simplest, including because it is naturally…
-
1
votes1
answer89
viewsA: Does not print numeric digits
You’re sending print number (%d), and want to print characters (%c), this is the mistake. Also I saved the size of the string in a variable because the function strlen() is extremely slow and should…
-
3
votes1
answer85
viewsA: Why use parameter modifiers?
Their functioning has already been described in What are the out and ref parameters (the example of ref is artificial and not very good, is the same of the question here) and What good is this 'in'…
-
1
votes1
answer85
viewsA: Why do space aliases only work with backticks?
Because space closes the identifier name. There are no space names. Identifiers are words, they must only have a name, so let’s say that there is a law that requires that you can only have a first…
-
5
votes2
answers2190
viewsA: Convert string to float on C#
All of these are wrong for the purpose described. If it is undetermined if the data is correct you cannot trust it, then it is normal if it is wrong, invalid, which cannot be converted, so the only…
-
4
votes1
answer317
viewsA: Is it better to make a large request to the database or several small ones?
We always say to these things that it depends, but in general to make a request that returns a large volume of data is better since the cost of each request in its various parts of transportation…
-
1
votes1
answer92
views -
1
votes3
answers246
viewsA: Read and print struct values
At no time does this code attempt to print something. Its main problem is that it is not passing the element by reference, then when you finish executing the insert function the data is lost. I…
-
6
votes2
answers144
viewsA: Where is the error in the leap year code?
That one for does not make sense from the point of view of syntax or logic, also does not make sense to give parseFloat() next year, something like this: function calcularBissexto(ano) { return ano…
-
21
votes1
answer929
viewsQ: What is the difference between code page, Plane, code point, octet and other terms about characters?
Considering the use of characters that we use to produce texts or other forms of visual representation we have some terms that we need to learn to use the various forms correctly. Has several…
-
3
votes2
answers1046
viewsA: What is the difference between KTS and KT extensions?
Kotlin supports execution in mode script more or less interpreted, so it is possible to execute something through a text, more or less as is possible in languages like C# through the .NET Compiler…
-
1
votes1
answer72
viewsA: How to leave default value in Static Arraylist in Java?
It is not true that there is no builder, it has an answer showing the use of static constructor. So it would be something like this (I don’t guarantee because there are no details of how it should…
-
5
votes1
answer61
viewsA: Do vectors and structures always have continuous addresses?
struct is something for you to group heterogeneous data that would be isolated to be treated as one thing, is to give cohesion to a type of object that you are creating, so what is the sense that…
-
4
votes1
answer3094
viewsA: "Warning comparison between Pointer and integer" - what is it?
The error is exactly what is written, as you declared the variable livro as a array, it becomes a pointer to a sequence of data, already TAM is a numerical constant. C is a static typing language,…
-
3
votes2
answers302
viewsA: Error trying to access an array element
Tam some errors in the code. The one that appears is that is trying to access an element of a array in something that is not a array. You declared a structure, and a variable with her type, but…
-
1
votes1
answer55
viewsA: Is it a problem for me to work only with reading a file with it open in both write and read mode?
These decisions depend on the real context. I know everybody wants a magic decision that works for everything, but it can’t be like this, if it wasn’t I wouldn’t need programmers, all problems would…
-
1
votes1
answer60
viewsA: Stringtokenizer with String delimiter does not work
Do not use this class, it is problematic, for simple cases it is easier to use split() of String even. class Program { public static void main(String[] args) { String text = "1 - -- * d 2"; String[]…
-
4
votes1
answer1047
viewsA: Zerodivisionerror: integer Division or modulo by zero
How the name says the function range() generates numbers within a defined range. If you put only one number this will be the final limit, and the beginning will be automatically 0, then you make a…