如何使用ifstream打开文件并继续阅读直到结束 [英] How to open a file using ifstream and keep reading it until the end

问题描述

我只是想打开一个名为"test.txt"的文件，其中包含:

I simply would like to open a file named "test.txt" that contains:

cat
dog
moose
rabbit

然后，我想从文件中读取内容并将其内容转换为字符串，以备稍后在程序中执行.到目前为止，我认为我正在做的事情朝着正确的方向发展.但是，我遇到错误，不确定该怎么办.这是错误>>>

I then want to read from the file and convert its contents into strings for things that I will do later in the program. So far i think what I am doing is going in the right direction. However, I am getting an error and I am unsure what to do. Here is the Error>>>

$ make -f makefile.txt
g++ -g -D HASH_TABLE_SIZE=10 -c hash.cpp
hash.cpp: In member function `void Hash::processFile(std::string)':
hash.cpp:12: error: no match for 'operator>>' in 'my_infile >> word'
makefile.txt:6: recipe for target `hash.o' failed
make: *** [hash.o] Error 1

这是我到目前为止拥有的代码(因此将无法编译)

Here is the code I have so far (it will not compile because of that)

void Hash::processFile(string filename)
{
    string word;
    Hash HashTable;

    ifstream my_infile(const char* filename, ios_base::openmode mode = ios_base::in);
    while(my_infile >> word)//iterate through the file and hash them (handles collisions too)
    {
        //Insert keys and handle collisions
    }

}

推荐答案

ifstream my_infile(const char* filename, ios_base::openmode mode = ios_base::in);

该行不是在创建std::ifstream的实例，而是在声明一个函数.

That line is not creating an instance of std::ifstream, it is declaring a function.

您需要的行是:

ifstream my_infile(filename);

这篇关于如何使用ifstream打开文件并继续阅读直到结束的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！