C++ string类基本用法样例

#define _CRT_SECURE_NO_DEPRECATE
#include <string>    // 使用 string 类时须包含这个文件
#include <iostream>

using namespace std;

int main()
{
    string str1;

    // 输入与输出
    cout << "输入字符串 str1" << endl;
    cin >> str1;
    getchar();
    cout << str1 << endl << endl << endl;

    // 一行行读取
    cout << "输入字符串 str1" << endl;
    getline( cin, str1 );
    cout << str1 << endl;

    // 与c字符转换
    string str2("Hello World!"), str3;
    char   str4[50];

    cout << "输入 C 字符串" << endl;
    scanf("%s", str4);
    str3= str4;

    cout << "str2 is " << str2 << endl;
    cout << "str3 is " << str3 << endl << endl << endl;

    // 求字符串的长度
    string str5;
    cout << "输入字符串 str5" << endl;
    cin >> str5;
    int   len= str5.size();
    cout << "字符串 str5的长度为" << len << endl << endl << endl;

    // 遍历字符串例子
    string str6;
    cout << "输入字符串 str6" << endl;
    cin >> str6;
    int i;
    for( i= 0; i< str6.size(); ++i )
        cout << str6[i];
    cout << endl << endl;

    // 比较两个字符串比较规则同 c字符串比较规则
    string str7, str8;
    cout << "输入字符串 str7, str8 , 中间用空格格开" << endl;
    cin >> str7 >> str8;

    if( str7< str8 ) cout << str7 << " 小于 " << str8 << endl;
    else if( str7> str8 ) cout << str7 << " 大于 " << str8 << endl;
    else cout << str7 << " 等于 " << str8 << endl;

    // 字符串与字符相加
    string str9= "Darren";
    char ch1= 'a', ch2= 'b';
    str9= str9+ ch1; cout << str9 << endl << endl;
    str9= ch2+ str9; cout << str9 << endl << endl << endl;

    // 字符串与字符串相加
    string str10= "Acm", str11= "ICPC";
    str10.append( str11 );
    cout << str10 << endl << endl;

    // 字符串是否包含子串如果包含则返回子串在目标串中第一次出现的位置
    string str12= "I am a student", str13= "student", str14= "aaaaaaa";
    if( str12.find( str13 )!= -1 ) cout << "Find " << str13 << endl;
    if( str12.find( str14 )== -1 ) cout << "Not Find " << str14 << endl;

    // 转换成 c_字符串
    string str15= "Hello World";
    printf("%s\n", str15.c_str() );

    system("pause");

    return 0;
}

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补充：软件开发 , C++ ,