c++中字符输入函数cin.getline在输入char与string时的不同

cin.getline在输入char时：

using namespace std;
    const int ArSize = 20;
    char name[ArSize];
    char dessert[ArSize];


    cout << "Enter your name:\n";
    cin.getline(name, ArSize);  // reads through newline
    cout << "Enter your favorite dessert:\n";
    cin.getline(dessert, ArSize);

getline在输入string时：

#include<iostream>
#include<string>
using namespace std;



int main()
{
    string name;
    string dessert;


    cout<<"Enter your name:\n";
    getline(cin,name);
    cout<<"Enter your favorite dessert:\n";
    getline(cin,dessert);