Question

我试图在C ++中的字符串向量上使用push_back。如何将单个字符推送到矢量？目前，我尝试了以下方法，但都没有成功：

使用该字符初始化一个字符串（尝试）。

代码

string str(main_string[0]);  
vector_string.push_back(str);

试图调用strcpy然后复制内容。稳定似乎阻碍了。

代码

string str;  
strcpy(main_string[0], str.c_str());  
vector_string.push_back(str);

欢迎任何更多的建议/想法。

编辑：错误日志如下：

test_push.C: In function ‘void test_push(std::vector<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::basic_string<char, std::char_traits<char>, std::allocator<char> > > >&, std::string)’:
test_push.C:50: error: no matching function for call to ‘std::basic_string<char, std::char_traits<char>, std::allocator<char> >::basic_string(char&)’
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:220: note: candidates are: std::basic_string<_CharT, _Traits, _Alloc>::basic_string(typename _Alloc::rebind<_CharT>::other::size_type, _CharT, const _Alloc&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:213: note:                 std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const _CharT*, const _Alloc&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>] <near match>
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:206: note:                 std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const _CharT*, typename _Alloc::rebind<_CharT>::other::size_type, const _Alloc&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:194: note:                 std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const std::basic_string<_CharT, _Traits, _Alloc>&, typename _Alloc::rebind<_CharT>::other::size_type, typename _Alloc::rebind<_CharT>::other::size_type, const _Alloc&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:184: note:                 std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const std::basic_string<_CharT, _Traits, _Alloc>&, typename _Alloc::rebind<_CharT>::other::size_type, typename _Alloc::rebind<_CharT>::other::size_type) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:170: note:                 std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const std::basic_string<_CharT, _Traits, _Alloc>&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:178: note:                 std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const _Alloc&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.h:2147: note:                 std::basic_string<_CharT, _Traits, _Alloc>::basic_string() [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]
test_push.C:61: error: conversion from ‘char’ to non-scalar type ‘std::string’ requested
test_push:90: error: no matching function for call to ‘std::basic_string<char, std::char_traits<char>, std::allocator<char> >::basic_string(char&)’
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:220: note: candidates are: std::basic_string<_CharT, _Traits, _Alloc>::basic_string(typename _Alloc::rebind<_CharT>::other::size_type, _CharT, const _Alloc&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:213: note:                 std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const _CharT*, const _Alloc&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>] <near match>
/usr/lib/gcc/i586-redhat-linux/4.4.1/../../../../include/c++/4.4.1/bits/basic_string.tcc:206: note:                 std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const _CharT*, typename _Alloc::rebind<_CharT>::other::size_type, const _Alloc&) [with _CharT = char, _Traits = std::char_traits<char>, _Alloc = std::allocator<char>]

更多信息：在此函数中，整个字符串或只是第一个字母根据其内容被推入向量。所以，在某种程度上，我正在寻找一些将char转换为C ++样式std::string的函数（使其可以被矢量接受）。

谢谢，
斯利拉姆

Answer 1

您也可以使用这样的一个字符初始化。

string str(1,main_string[0]);  
vector_string.push_back(str);

Answer 2

您可以通过适当的字符串构造函数直接添加字符：

vector_string.push_back(string(1, main_string[0]));

编辑：在意识到它重复@Tim's后删除了备用解决方案。

Answer 3

单个角色不需要strcpy。

string str ("x");
str[0] = main_string[0]; 
vector_string.push_back(str);

在字符串向量上使用push_back - C ++

3 个答案: