std::basic_ios::operator!
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bool operator!()const; | ||
Retorna true se ocorreu um erro no fluxo associado. Especificamente, os retornos true se
badbit ou failbit é definido em rdstate().Original:
Returns true if an error has occurred on the associated stream. Specifically, returns true if
badbit or failbit is set in rdstate().The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
Índice |
[editar]Parâmetros
(Nenhum)
Original:
(none)
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
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[editar]Valor de retorno
true se um erro ocorreu, false outra forma.
Original:
true if an error has occurred, false otherwise.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
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[editar]Exemplo
#include <iostream>#include <fstream>#include <cstdlib>int main(){std::ifstream file("test.txt");if(!file)// operator! is used here{std::cout<<"File opening failed\n";returnEXIT_FAILURE;} // typical C++ I/O loop uses the return value of the I/O function// as the loop controlling condition, operator bool() is used herefor(int n; file >> n;){std::cout<< n <<' ';}std::cout<<'\n'; if(file.bad())std::cout<<"I/O error while reading\n";elseif(file.eof())std::cout<<"End of file reached successfully\n";elseif(file.fail())std::cout<<"Non-integer data encountered\n";}
[editar]Veja também
| ios_base::iostate flags | basic_ios accessors | |||||||
| eofbit | failbit | badbit | good() | fail() | bad() | eof() | operator bool() | operator!() |
| false | false | false | true | false | false | false | true | false |
| false | false | true | false | true | true | false | false | true |
| false | true | false | false | true | false | false | false | true |
| false | true | true | false | true | true | false | false | true |
| true | false | false | false | false | false | true | true | false |
| true | false | true | false | true | true | true | false | true |
| true | true | false | false | true | false | true | false | true |
| true | true | true | false | true | true | true | false | true |
