Delete tabs as well as spaces in c++

Question

I wrote the following c++ code which removes spaces from beginning and end of a string, But the problem with it is that it doesn't remove tabs, how may I fix that?

Plus, is there anything similar to tabs and spaces? (I am reading lines from file)

string trim_edges(string command) {
    const auto command_begin = command.find_first_not_of(' ');
    if (command_begin == std::string::npos)
        return "";

    const auto strEnd = command.find_last_not_of(' ');
    const auto strRange = strEnd - command_begin + 1;

    return command.substr(command_begin, strRange);
}

You might want to take a look at [What's the best way to trim std::string?](https://stackoverflow.com/questions/216823/whats-the-best-way-to-trim-stdstring) and [std::isspace](https://en.cppreference.com/w/cpp/string/byte/isspace) — t.niese, Aug 04 '20 at 08:50

score 8 · Answer 1 · answered Aug 04 '20 at 08:32

8

find_first_not_of and find_last_not_of can also take a string as a set of characters to skip:

const auto command_begin = command.find_first_not_of(" \t");
const auto strEnd = command.find_last_not_of(" \t");

answered Aug 04 '20 at 08:32

Botje

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what the full code will look like? it seems you deleted return "" – Aug 04 '20 at 08:34
Thanks, is there anything similar to spaces that need to e removed? like tabs and so on? – Aug 04 '20 at 08:36
You could draw inspiration from [std::isspace](https://devdocs.io/cpp/string/byte/isspace) – Botje Aug 04 '20 at 08:40
@daniel For ASCII you could probably remove all chars `<= ' '` - otherwise, `"\a\b\f\n\r\t\v "` - See [Escape sequences](https://en.cppreference.com/w/cpp/language/escape) – Ted Lyngmo Aug 04 '20 at 08:42
@TedLyngmo what are those \a\b they aren't mentioned – Aug 04 '20 at 09:38
1

They are mentioned in the link @TedLyngmo posted. – Botje Aug 04 '20 at 09:44

Delete tabs as well as spaces in c++

1 Answers1