用於顯示字符串|的每個字符的循環C++

Question

我想知道如何控制字符串並從字符串中獲取字符。
這裏是我的代碼：

#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); 
    } 
} 

此輸出如下：

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!! 

什麼是去朝着正確的方向？我該如何解決這個問題？

Answer 1

std::basic_string::substr被用於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; 
} 

此輸出

   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; 

}