C/C++中字符串流详解及其作用介绍

目录

• 概述
• 字符串流
• 理解字符串流
• 输出字符串对象
• 输入字符串流对象
• 输入输出字符串流对象
• 案例一
• 案例二
• 字符数组 vs 文件
• 总结

#include <iostream>
using namespace std;
int main() {
    double m, n;
    char op;
    cin >> m >> op >> n;
    cout << m << " " << n << " " << op;
    return 0;
}

ostrstream::ostrstream(char *buffer, int n, int mode=ios::out);

char ch1[20];
ostrstream strout(ch1, 20);

istrstream::istrstream(char *buffer);
istrstream::istrstream(char *buffer, int n);

char ch2[40];
istrstream strin(ch2);  // 将字符数组ch2中的全部数据作为输入字符串流的内容
istrstream strin(ch2,20);  // 只将字符数组ch2中的前20个字符作为输入字符串流的内容

strstream::strstream(char *buffer, int n, int mode);

char ch3[80];
strstream strio(ch3, sizeof(ch3), ios::in|ios::out);

#include <iostream>
#include <strstream>
#include "Student.h"
using namespace std;
int main( )
{
    // 定义数组
    Student stud[3]= {
            {1001, "Little"},
            {1002, "Mid"},
            {1003, "Big"},
    };
    char c[50];  // 定义char数组存放字符流
    ostrstream strout1(c, 30);
    for(int i = 0; i < 3; i++)
        strout1 << stud[i].id << stud[i].name;
    strout1 << ends; // ends是C++的I/O操作符，插入一个′\0′
    cout << "array c:" << c << endl;
    ostrstream strout2(c, 40);
    for(int i = 0; i < 3; i++)
        strout2 << stud[i].id << " " << stud[i].name << " ";
    strout2 << ends;
    cout << "array c:" << c << endl;
    return 0;
}

#include <iostream>
#include <strstream>
using namespace std;
int* bubble_sort(int array[10]);
void display(int array[10]);
int main() {
    // 定义数组
    char c[50] = "23 45 56 -23 -32 33 61 99 88 77";
    int a[10], *pt;
    // 输入字符串流
    cout << "array c: " << c << endl;
    istrstream strin(c, sizeof(c));
    for (int i = 0; i < 10; i++) {
        strin >> a[i];
    }
    // 调试输出
    cout << "array a: ";
    display(a);
    cout << endl;
    // 对数组 a 排序进行冒泡排序
    pt = bubble_sort(a);
    // 输出字符串流
    ostrstream strout(c, sizeof(c));
    for (int i = 0; i < 10; ++i) {
        strout << *(pt+i) << " ";
    }
    cout << "array c: " << c << endl;
    return 0;
}