变量在迭代时不打印 [英] Variable not printing on iteration

问题描述

我为个人项目编写了一个C ++ CSV类，但却发现了一个奇怪的错误。在我的测试程序我有代码：

I'm writing a C++ CSV class for a personal project, but have stumbled on a weird error. In my test program I have the code:

for( int i = 0; i < 3; ++i ) {
    std::cout << i << ": ";
    std::vector<std::string> results = test.get_row();
    for( auto it = results.begin(); it != results.end(); ++it ) {
        std::cout << *it << " ";
    }
    std::cout << std::endl;
}

并获得结果：

 : row0 row1 row2
 : blah0 blah1 blah2
2: blah3 blah4 blah5

但我应该得到：

0: row0 row1 row2
1: blah0 blah1 blah2
2: blah3 blah4 blah5

我在前两次运行时没有得到 i 值？

Any ideas as to why I'm not getting the i value on the first two runs?

注意：我使用g ++ 4.4 .7

Note: I'm using g++ 4.4.7

推荐答案

啊。我想我看到了：

您似乎忘记了从输入中删除换行符。

You appear to have forgotten to strip the newlines from the input.

这将导致最后一列具有尾随'\r'，并且由于始终添加一个覆盖最初打印的 i 。

This would resulting in the last column having a trailing '\r', and since you always add a ' ', this space will overwrite the originally printed i.

在拆分列值之前从输入中剥离换行符：

Strip the newline character from the input before splitting columns values :)

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