使用 ifstream 和 getline 读取文件内容[c++] #include #include #include using namespace std; //输出空行 void OutPutAnEmptyLine() { cout<<"\n"; } //读取方式: 逐词读取, 词之间用空格区分 //read data from the file, Word By Word //when used in this manner, we'll get space-delimited bits of text from the file //but all of the whitespace that separated words (including newlines) was lost. void ReadDataFromFileWBW() { ifstream fin("data.txt"); string s; while( fin >> s ) { cout << "Read from file: " << s << endl; } } //读取方式: 逐行读取, 将行读入字符数组, 行之间用回车换行区分 //If we were interested in preserving whitespace, //we could read the file in Line-By-Line using the I/O getline() function. void ReadDataFromFileLBLIntoCharArray() { ifstream fin("data.txt"); const int LINE_LENGTH = 100; char str[LINE_LENGTH]; while( fin.getline(str,LINE_LENGTH) ) { cout << "Read from file: " << str << endl; } } //读取方式: 逐行读取, 将行读入字符串, 行之间用回车换行区分 

//If you want to avoid reading into character arrays, //you can use the C++ string getline() function to read lines into strings void ReadDataFromFileLBLIntoString() { ifstream fin("data.txt"); string s; while( getline(fin,s) ) { cout << "Read from file: " << s << endl; } } //带错误检测的读取方式 //Simply evaluating an I/O object in a boolean context will return false //if any errors have occurred void ReadDataWithErrChecking() { string filename = "dataFUNNY.txt"; ifstream fin( filename.c_str()); if( !fin ) { cout << "Error opening " << filename << " for input" << endl; exit(-1); } } int main() { ReadDataFromFileWBW(); //逐词读入字符串 OutPutAnEmptyLine(); //输出空行 ReadDataFromFileLBLIntoCharArray(); //逐词读入字符数组 OutPutAnEmptyLine(); //输出空行 ReadDataFromFileLBLIntoString(); //逐词读入字符串 OutPutAnEmptyLine(); //输出空行 ReadDataWithErrChecking(); //带检测的读取 return 0; } 输出结果为: Read from file: Fry: Read from file: One 

Read from file: Jillion Read from file: dollars. Read from file: [Everyone Read from file: gasps.] Read from file: Auctioneer: Read from file: Sir, Read from file: that's Read from file: not Read from file: a Read from file: number. Read from file: 数据读取， Read from file: 测试 Read from file: 。 Read from file: Fry: One Jillion dollars. Read from file: [Everyone gasps.] Read from file: Auctioneer: Sir, that's not a number. Read from file: 数据读取， 测试 。 Read from file: Fry: One Jillion dollars. Read from file: [Everyone gasps.] Read from file: Auctioneer: Sir, that's not a number. Read from file: 数据读取， 测试 。 Error opening dataFUNNY.txt for input Press any key to continue