C++ primer 第3章 ex3.10

#pragma once
#include <string>
#include <iostream>
#include <cctype>
using namespace std;

void getstring()
{

	string result_str,userInput_str;
	bool hasPunct=false;
	cout<<"请输入字符传："<<endl;
	cin>>userInput_str;
	for(string::size_type i=0;i<userInput_str.size();i++)
	{
		char check=userInput_str[i];
		if (ispunct(check))
		{
			hasPunct=true;
		}
		else
		{
			result_str += check;
		}

	}
	if (hasPunct)
	{
		cout<<"去标点后的字符串："<<result_str<<endl;
	}else
	{
		cout<<"输入有误，输入必须包含标点！"<<endl;
	}

}

int main()
{
   
	while(true)
	{
	
		cout << endl << "1) 输出去标点后的字符串" << endl;
		cout << "2) 退出" << endl << endl;
		cout << "请选择 [1], [2] : ";
		string userInput; 
		
		getline(cin,userInput);
		
		if(userInput.size() == 0) continue;

		const char ch = userInput[0];

		if(ch == '2') break;
		else if(ch =='1') getstring();
	
		else cout << endl << "Input error. Enter 1, 2 and [Enter]."<< endl;
	}
return 0;
}