C++获取文本文件字节数
作者:admin 发布于:2012-8-9 10:47 Thursday 分类:Windows
1 调用ifstream打开一个文件
2 调用seekg将get pointer置为文件末尾,seekg(0, ios_base::end)
3 调用tellg获取总字节数,实际上获取的是get pointer相对于文件头的偏移字节数
4 重置get pointer,使其指向文件头,以便执行其他操作
对于ifstream对象的每一次read过后,可以调用ifstream::gcount获取读取的字节数,
gcount的返回值为streamsize,而streamsize是个整型,signed int或signed long
#include <iostream> #include <fstream> using namespace std; int main () { int length; char * buffer; ifstream is; is.open ("test.txt", ios::binary ); // get length of file: is.seekg (0, ios::end); length = is.tellg(); is.seekg (0, ios::beg); // allocate memory: buffer = new char [length]; // read data as a block: is.read (buffer,length); is.close(); cout.write (buffer,length); return 0; }