c++ string 類基本用法樣例
阿新 • • 發佈:2019-02-12
#include
<
string
>
//
使用 string 類時須包含這個檔案
#include
<
iostream
>
using
namespace
std;
int
main()
{
string
str1;
//
輸入與輸出
cout
<<
"
輸入字串 str1
"
<<
endl;
cin
>>
str1; getchar();
cout
<<
str1
<<
endl
<<
endl
// 一行行讀取 cout << " 輸入字串 str1 " << endl;
getline( cin, str1 );
cout << str1 << endl;
// 與 c字元轉換 string str2( " Hello World! " ), str3;
char str4[ 50 ];
cout << " 輸入 C 字串 " << endl;
scanf( "
str3 = str4;
cout << " str2 is " << str2 << endl;
cout << " str3 is " << str3 << endl << endl << endl;
// 求字串的長度 string str5;
cout << " 輸入字串 str5 " << endl;
cin >> str5;
cout << " 字串 str5的長度為 " << len << endl << endl << endl;
// 遍歷字串例子 string str6;
cout << " 輸入字串 str6 " << endl;
cin >> str6;
int i;
for ( i = 0 ; i < str6.size(); ++ i )
cout << str6[i];
cout << endl << endl;
// 比較兩個字串 比較規則同 c字串比較規則 string str7, str8;
cout << " 輸入字串 str7, str8 , 中間用空格格開 " << endl;
cin >> str7 >> str8;
if ( str7 < str8 ) cout << str7 << " 小於 " << str8 << endl;
else if ( str7 > str8 ) cout << str7 << " 大於 " << str8 << endl;
else cout << str7 << " 等於 " << str8 << endl;
// 字串與字元相加 string str9 = " Darren " ;
char ch1 = ' a ' , ch2 = ' b ' ;
str9 = str9 + ch1; cout << str9 << endl << endl;
str9 = ch2 + str9; cout << str9 << endl << endl << endl;
// 字串與字串相加 string str10 = " Acm " , str11 = " ICPC " ;
str10.append( str11 );
cout << str10 << endl << endl;
// 字串是否包含子串 如果包含 則返回子串在目標串中第一次出現的位置 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;
// 轉換成 c_字串 string str15 = " Hello World " ;
printf( " %s/n " , str15.c_str() );
system( " pause " );
return 0 ;
}