Looping through the characters of a std::string, using a range-based for loop (it's from C++11, already supported in recent releases of GCC, clang, and the VC11 beta): std::string str = ???; for(char& c : str) { do_things_with(c); } Looping through the characters of a std::string with iterators: std::string str = ???; for(std::string::iterator it = str.begin(); it != str.end(); ++it) { do_things_with(*it); } Looping through the characters of a std::string with an old-fashioned for-loop: std::string str = ???; for(std::string::size_type i = 0; i < str.size(); ++i) { do_things_with(str[i]); } Looping through the characters of a null-terminated character array: char* str = ???; for(char* it = str; *it; ++it) { do_things_with(*it); }

这是另一种方法，使用标准算法。

#include <iostream>
#include <string>
#include <algorithm>

int main()
{
   std::string name = "some string";
   std::for_each(name.begin(), name.end(), [] (char c) {
      std::cout << c;
   });
}

你可以通过使用字符串库中的at函数来获取字符串中的每一个char，就像我这样做的

string words;
    for (unsigned int i = 0; i < words.length(); i++)
        {
            if (words.at(i) == ' ')
            {
                spacecounter++;    // to count all the spaces in a string
                if (words.at(i + 1) == ' ')
                {
                    i += 1;
                }

这只是我的一段代码重点是你可以通过stringname。at(index)访问字符

for (int x = 0; x < yourString.size();x++){
        if (yourString[x] == 'a'){
            //Do Something
        }
        if (yourString[x] == 'b'){
            //Do Something
        }
        if (yourString[x] == 'c'){
            //Do Something
        }
        //...........
    }

String基本上是一个字符数组，因此您可以指定索引来获取字符。如果您不知道索引，那么您可以像上面的代码一样对其进行循环，但是当您进行比较时，请确保使用单引号(它指定一个字符)。

除此之外，上面的代码是自解释的。

Looping through the characters of a std::string, using a range-based for loop (it's from C++11, already supported in recent releases of GCC, clang, and the VC11 beta): std::string str = ???; for(char& c : str) { do_things_with(c); } Looping through the characters of a std::string with iterators: std::string str = ???; for(std::string::iterator it = str.begin(); it != str.end(); ++it) { do_things_with(*it); } Looping through the characters of a std::string with an old-fashioned for-loop: std::string str = ???; for(std::string::size_type i = 0; i < str.size(); ++i) { do_things_with(str[i]); } Looping through the characters of a null-terminated character array: char* str = ???; for(char* it = str; *it; ++it) { do_things_with(*it); }

对于C-string (char[])，你应该这样做:

char mystring[] = "My String";
int size = strlen(mystring);
int i;
for(i = 0; i < size; i++) {
    char c = mystring[i];
}

对于std::string，你可以使用str.size()来获取它的大小并像示例一样迭代，或者可以使用迭代器:

std::string mystring = "My String";
std::string::iterator it;
for(it = mystring.begin(); it != mystring.end(); it++) {
    char c = *it;
}