这个用起来可能更好

void replace(string& input, const string& from, const string& to)
{
    auto pos = 0;
    while(true)
    {
        size_t startPosition = input.find(from, pos);
        if(startPosition == string::npos)
            return;
        input.replace(startPosition, from.length(), to);
        pos += to.length();
    }
}

要返回新字符串，请使用以下命令:

std::string ReplaceString(std::string subject, const std::string& search,
                          const std::string& replace) {
    size_t pos = 0;
    while ((pos = subject.find(search, pos)) != std::string::npos) {
         subject.replace(pos, search.length(), replace);
         pos += replace.length();
    }
    return subject;
}

如果你需要性能，这里有一个修改输入字符串的优化函数，它不会创建字符串的副本:

void ReplaceStringInPlace(std::string& subject, const std::string& search,
                          const std::string& replace) {
    size_t pos = 0;
    while ((pos = subject.find(search, pos)) != std::string::npos) {
         subject.replace(pos, search.length(), replace);
         pos += replace.length();
    }
}

测试:

std::string input = "abc abc def";
std::cout << "Input string: " << input << std::endl;

std::cout << "ReplaceString() return value: " 
          << ReplaceString(input, "bc", "!!") << std::endl;
std::cout << "ReplaceString() input string not modified: " 
          << input << std::endl;

ReplaceStringInPlace(input, "bc", "??");
std::cout << "ReplaceStringInPlace() input string modified: " 
          << input << std::endl;

输出:

Input string: abc abc def
ReplaceString() return value: a!! a!! def
ReplaceString() input string not modified: abc abc def
ReplaceStringInPlace() input string modified: a?? a?? def

使用std:: string::替换:

s.replace(s.find("$name"), sizeof("$name") - 1, "Somename");

您可以使用此代码删除减法，也可以替换，也可以删除额外的空白。 代码:

#include<bits/stdc++.h>
using namespace std;

void removeSpaces(string &str)
{   
    int n = str.length();
    int i = 0, j = -1;

    bool spaceFound = false;
    while (++j <= n && str[j] == ' ');

    while (j <= n)
    {
        if (str[j] != ' ')
        {
          
            if ((str[j] == '.' || str[j] == ',' ||
                 str[j] == '?') && i - 1 >= 0 &&
                 str[i - 1] == ' ')
                str[i - 1] = str[j++];
            else str[i++] = str[j++];
 
            spaceFound = false;
        }
        else if (str[j++] == ' ')
        {
            if (!spaceFound)
            {
                str[i++] = ' ';
                spaceFound = true;
            }
        }
    }

    if (i <= 1)
         str.erase(str.begin() + i, str.end());
    else str.erase(str.begin() + i - 1, str.end());
}
int main()
{
    string s;
    cin >> s;

    for(int i = s.find("WUB"); i >= 0; i = s.find("WUB"))
        s.replace(i,3," ");
    removeSpaces(s);
    cout << s << endl;

    return 0;
}

我现在正在学习c++，但是编辑之前发布的一些代码，我可能会使用这样的东西。这为您提供了替换一个或多个实例的灵活性，还允许您指定起始点。

using namespace std;

// returns number of replacements made in string
long strReplace(string& str, const string& from, const string& to, size_t start = 0, long count = -1) {
    if (from.empty()) return 0;

    size_t startpos = str.find(from, start);
    long replaceCount = 0;

    while (startpos != string::npos){
        str.replace(startpos, from.length(), to);
        startpos += to.length();
        replaceCount++;

        if (count > 0 && replaceCount >= count) break;
        startpos = str.find(from, startpos);
    }

    return replaceCount;
}

我自己的实现，考虑到字符串只需要调整一次大小，然后替换就可以发生。

template <typename T>
std::basic_string<T> replaceAll(const std::basic_string<T>& s, const T* from, const T* to)
{
    auto length = std::char_traits<T>::length;
    size_t toLen = length(to), fromLen = length(from), delta = toLen - fromLen;
    bool pass = false;
    std::string ns = s;

    size_t newLen = ns.length();

    for (bool estimate : { true, false })
    {
        size_t pos = 0;

        for (; (pos = ns.find(from, pos)) != std::string::npos; pos++)
        {
            if (estimate)
            {
                newLen += delta;
                pos += fromLen;
            }
            else
            {
                ns.replace(pos, fromLen, to);
                pos += delta;
            }
        }

        if (estimate)
            ns.resize(newLen);
    }

    return ns;
}

用法可以是这样的:

std::string dirSuite = replaceAll(replaceAll(relPath.parent_path().u8string(), "\\", "/"), ":", "");