stl取出字符串中的字符

字符串作为数据类型 (String as datatype)

In C, we know string basically a character array terminated by \0. Thus to operate with the string we define character array. But in C++, the standard library gives us the facility to use the string as a basic data type like an integer. But the string characters can be still accessed considering the string as a character array.

在C语言中，我们知道字符串基本上是一个以\ 0结尾的字符数组。 因此，要对字符串进行操作，我们定义了字符数组。 但是在C ++中，标准库为我们提供了将字符串用作基本数据类型(如整数)的便利。 但是，仍可以将字符串视为字符数组来访问字符串字符。

Example:

例：

    Like we define and declare,
string s="IncludeHelp";
s[0] = 'I' (not "I")
s[7] = 'H'
//So same way we can access the string element which is character.
//Also there is a function under string class, at(),
//which can be used for the same purpose.
cout << s.at(7); //prints H

Remember, a string variable (literal) need to be defined under "". 'a' is a character whereas "a" is a string.

请记住，需要在“”下定义一个字符串变量(文字)。 “ a”是字符，而“ a”是字符串。

Note: Trying to accessing character beyond string length results in segmentation fault.

注意：尝试访问超出字符串长度的字符会导致分段错误。

Header file needed:

所需的头文件：

    #include <string>
Or
#include <bits/stdc++.h>

C++ program to demonstrate example of accessing characters of a string

C ++程序演示访问字符串字符的示例

#include <bits/stdc++.h>
using namespace std;
int main(){string s;
cout<<"enter string...\n";
cin>>s;
cout<<"Printing all character elements...\n";
for(int i=0;i<s.length();i++)
cout<<s[i]<<" ";
return 0;
}

Output

输出量

enter string...
IncludeHelp
Printing all character elements...
I n c l u d e H e l p

翻译自: https://www.includehelp.com/stl/accessing-character-elements-from-a-string-in-cpp-stl.aspx

stl取出字符串中的字符