迭代向量,并删除某些项目?

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一旦使用迭代器擦除,所有迭代器都会失效。

 std::vector<std::string> iter = m_vPaths.begin();
    for( ; iter != m_vPaths.end(); iter++) {
        std::string strPath = *iter;
        if(::DeleteFile(strPath.c_str())) {
            m_vPaths.erase(iter);   
                //Now my interators are invalid because I used erase,
                //but I want to continue deleteing the files remaining in my vector.    
        }
    }

提问于
用户回答回答于

检查std::remove_if:

#include <algorithm> // for remove_if
#include <functional> // for unary_function

struct delete_file : public std::unary_function<const std::string&, bool> 
{
    bool operator()(const std::string& strPath) const
    {
        return ::DeleteFile(strPath.c_str());
    }
}

m_vPaths.erase(std::remove_if(m_vPaths.begin(), m_vPaths.end(), delete_file()),
                m_vPaths.end());

实现代码的方式是:

typedef std::vector<std::string> string_vector;
typedef std::vector<std::string>::iterator string_vector_iterator;

string_vector_iterator iter = m_vPaths.begin();
while (iter != m_vPaths.end())
{
    if(::DeleteFile(iter->c_str()))
    {
        // erase returns the new iterator
        iter = m_vPaths.erase(iter);
    }
    else
    {
        ++iter;
    }
}

用户回答回答于

erase()方法返回一个新的(有效)迭代器可以使用此迭代器继续循环:

std::vector<std::string>::iterator iter;
for (iter = m_vPaths.begin(); iter != m_vPaths.end(); ) {
    if (::DeleteFile(iter->c_str()))
        iter = m_vPaths.erase(iter);
    else
        ++iter;
}

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