C++ “ofstream”作为函数参数
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/9658720/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
"ofstream" as function argument
提问by Shibli
Is there a way to pass output stream as argument like
有没有办法将输出流作为参数传递
void foo (std::ofstream dumFile) {}
void foo (std::ofstream dumFile) {}
I tried that but it gave
我试过了，但它给了
error : class "std::basic_ofstream<char, std::char_traits<char>>" has no suitable copy constructor
error : class "std::basic_ofstream<char, std::char_traits<char>>" has no suitable copy constructor
回答by Boris Strandjev
Of course there is. Just use reference. Like that:
当然有。只用参考。像那样：
void foo (std::ofstream& dumFile) {}
Otherwise the copy constructor will be invoked, but there is no such defined for the class ofstream.
否则将调用复制构造函数，但没有为 class 定义这样的构造函数ofstream。
回答by Joel Falcou
You have to pass a reference to the ostreamobject as it has no copy constructor:
您必须传递对该ostream对象的引用，因为它没有复制构造函数：
void foo (std::ostream& dumFile) {}
回答by Mankarse
If you are using a C++11 conformant compiler and standard library, it should be ok to use
如果您使用的是符合 C++11 的编译器和标准库，则应该可以使用
void foo(std::ofstream dumFile) {}
as long as it is called with an rvalue. (Such calls will look like foo(std::ofstream("dummy.txt")), or foo(std::move(someFileStream))).
只要它是用右值调用的。（这样的调用看起来像foo(std::ofstream("dummy.txt")), 或foo(std::move(someFileStream))）。
Otherwise, change the parameter to be passed by reference, and avoid the need to copy/move the argument:
否则，更改为通过引用传递的参数，并避免需要复制/移动参数：
void foo(std::ofstream& dumFile) {}
