std::string is the C++ standard library's byte-based "string" type, defined in the
Questions tagged [stdstring]
1177 questions
-3
votes
2 answers
Sizeof is a negative number when I try to find out the length of a string
In my code, I've been trying to find the length of a specific string in a string array. However, when I do it, no matter what method I try to find the length of the specific string, always returns -858993460
The code I've been working with is
void…
JoeyChor
- 63
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- 7
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votes
1 answer
Assigning a std::basic_string to a string
I have the following existing class in my code:
struct Aclass {
typedef std::string TitleType;
TitleType title;
typedef std::size_t NumType;
NumType some_num;
};
After an instantiation of Aclass, let's say aclass, I set aclass.title…
Kevin
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-3
votes
2 answers
C++ - Unable to convert from std::basic string to bool
I am trying to build a simple authentication mechanism whereby the user inputs his login credentials and his input is then compared to content in a file 'UserDB.txt'. However, when i try to iterate through the file and compare his credentials with…
Jared Aaron Loo
- 668
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- 18
-4
votes
2 answers
Difference between string literal and string in cout statement?
What is the difference between the following ways of printing a string?
std::cout << "hello";
// and
std::cout << std::string("hello");
They both appear to do the same thing.
MaskOryle
- 31
- 4
-4
votes
3 answers
Why std::string seem to do something that std::is_convertible says isn't possible?
Why does std::to_string allow you to convert a double to std::string when std::is_convertible_v is false? For example:
#include
#include
#include
int main()
{
std::cout << "If double is "
…
Dimitrije Kostic
- 265
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-4
votes
1 answer
This program return nothing
I am trying to write the following code so that it might return Hello, World!.
using std::string;
using namespace std;
std::string hello()
{
return "Hello, World!";
}
int main()
{
hello();
return 0;
}
having the code compiler run with 0…
prof_shadi
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- 2
-4
votes
2 answers
How to resolve declaration errors
I am attempting to run a code that takes a user inputted standard time and convert it to military time. For the user input, the hours can be typed as one or two digits, and AM/PM can be typed in any way. Given that, the code I have is as…
Cynderias
- 5
- 3
-4
votes
3 answers
std::string::find returns wrong answer
There are some posts concerning std::string::find (like this one here and this one too) but I have a somewhat different situation:
#include
#include
int main(int argc, char **argv)
{
std::string haystack =…
OrenIshShalom
- 5,974
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- 87
-4
votes
2 answers
Initialization of std::string from std::vector causes error
In C++ we can create a vector from another vector via
std::vector tmp_1 { &some_vector[i] , &some_vector[j] };
Question : Is there any way to do the same for std::string?
Something like:
std::string tmp2 { &some_vector[i] ,…
Serhii S.
- 51
- 9
-4
votes
2 answers
get all the std::string's or first word's before character '='
I wanted to retrieve all the values/words before '='
Ex:
A = my first variable, I wanted to get all the strings;
var2 = I wanted to get this variable also;
var3 = jcdksjfckjdsckjdscjkdsbckjdsncjsjd;
Now I wanted to retrieve all the…
NDestiny
- 1,133
- 1
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- 28
-4
votes
3 answers
'std::string' has no member named 'username' error
My code won't compile because of a 'std::string' has no member named 'username' error. I'm using code::blocks. I'm guessing the problem is because I'm trying to assign a string to a class, can someone help?
#include
#include…
Satki
- 99
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- 11
-4
votes
1 answer
Lack of Implicit Conversions for Strings and STL Containers
Why doesn't C++ have implicit conversion to bool defined for std::string and STL containers when writing code like
if (!x.empty()) { ... }
instead of more shorter
if (x) { ... }
when x is of type std::string or for example std::vector?
I'm also…
Nordlöw
- 11,838
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- 99
-5
votes
2 answers
hot to convert std::__cxx11::string to std::string
so i just want to convert int in digits and store it in array
for eg
int n=456;
std::string nstr = std::to_string(n);
std::cout << nstr[0];
now i just want the length of nstr...
whenever i am using std::strlen(nstr);
its giving an error
**error:…
Aadi Manchekar
- 9
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-5
votes
1 answer
Which string constructor is invoked?
I know this is initialization but I am confused which of the 2 constructors is invoked when a string literal is used in each case. Are they both copy constructors?
string::string(const string& strString)
string::string(const char…
softwarelover
- 1,009
- 1
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- 22
-5
votes
1 answer
How does reversing a std::string in C++ works with this constructor?
std::string original;
std::string reversed(original.rbegin(), original.rend());
I have found this method for reversing a std::string but I don't understand how it works. Can you provide me with an explanation?
John
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