用于显示字符串|的每个字符的循环C++

Question

我想知道如何控制字符串并从字符串中获取字符。
这里是我的代码：

#include <iostream> 
#include <string> 

using namespace std; 

int mainMenu(); 

int main() { 
    mainMenu(); 
} 

int mainMenu(){ 
    string introText = "Welcome... Let me know your name!"; 
    cout << "\t\t\t"; 
    for (int i = 0; i <= introText.length(); i++){ 
     unsigned controller = i + 1; 
     cout <<introText.substr(i,controller); 
    } 
} 

此输出如下：

Wellcocomeome..me... e... Le... Let .. Let me. Let me k Let me knoLet me know et me know yot me know your me know your nme know your name know your name! know your name!know your name!now your name!ow your name!w your name! your name!your name!our name!ur name!r name! name!name!ame!me!e!! 

什么是去朝着正确的方向？我该如何解决这个问题？

Answer 1

std::basic_string::substr被用于提取一字符串的一部分。如果你想打印字符串的字符每次，你可以只使用std::basic_string::operator[]或std::basic_string::at：

for (int i = 0; i < introText.length(); i++){ 
    cout <<introText[i]; // or cout <<introText.at(i); 
} 

Answer 2

#include <iostream> 
#include <string> 

using namespace std; 

int mainMenu(); 

int main() { 
    mainMenu(); 
} 

int mainMenu(){ 
    string introText = "Welcome... Let me know your name!"; 
    cout << "\t\t\t"; 
    for (int i = 0; i < introText.length(); i++){ 
     //unsigned controller = i + 1; 
     //cout <<introText.substr(i,controller); 
     cout << introText[i]; 
    } 
     cout << endl; 
} 

此输出

   Welcome... Let me know your name! 

只需使用introText[i]

Answer 3

int mainMenu(){ 
string introText = "Welcome... Let me know your name!"; 
cout << "\t\t\t"; 
for (int i = 0; i < introText.length(); i++){ 

    cout << introText[i]; 
} 
    cout << endl; 

}