始）替换本字符串中的字符，从index1开始，最多num1个字符?
3.用str中的num个字符（从index开始）替换本字符串中的字符?
4.用str中的num2个字符（从index2开始）替换本字符串中的字符，从index1开始，num1个字符?
5.用num2个ch字符替换本字符串中的字符，从index开始?
6.用str中的字符替换本字符串中的字符,迭代器start和end指示范围?
7.用str中的num个字符替换本字符串中的内容,迭代器start和end指示范围，?
8.用num个ch字符替换本字符串中的内容，迭代器start和end指示范围.?
*/?
void test4()?
{????
??? string s = "They say he carved it himself...from a BIGGER spoon";?
??? string s2 = "find your Homer.";?
??? s.replace( 32, s2.length(), s2 );?
??? cout << s << endl;?? //They say he carved it himself...find your Homer.oon??
}???
//其他??
/*
交换(swap)? void swap( basic_string &str );//把str和本字符串交换
?
basic_string substr( size_type index, size_type num = npos );
substr()返回本字符串的一个子串，从index开始，长num个字符。如果没有指定，将是默认值 string::npos。这样，substr()函数将简单的返回从index开始的剩余的字符串。
?
size_type size();//size()函数返回字符串中现在拥有的字符数。
size_type length();//length()函数返回字符串的长度. 这个数字应该和size()返回的数字相同.
?
void clear();//清空
bool empty();//如果字符串为空则empty()返回真(true)，否则返回假(false).
?
const char *data();//data()函数返回指向自己的第一个字符的指针.
const char *c_str();//c_str()函数返回一个指向正规C字符串的指针, 内容与本字符串相同.?
*/?
void test5()?
{????
??? string first( "This comes first" );?
??? string second( "And this is second" );?
??? first.swap( second );?
??? cout << first << endl;//And this is second??
??? cout << second << endl;//This comes first??
?
??? string s("What we have here is a failure to communicate");?
??? string sub = s.substr(5);??
??? cout << sub << endl;//we have here is a failure to communicate??
?
??? cout<<"sub size:"< ?????????
??? sub.clear();//<==>sub="";??
??? cout< }??
//C++11??
//转换成 int;float;double;long;long long;long double;unsigned long;unsigned long long;??
//stoi(),stof(),stod(),stold(),stol(),stoll(),stoul(),stoull(),??
void test6()?
{?????
??? const char *str1 = " 42";?
??? const char *str2 = "3.14159";?
??? const char *str3 = "31337 with words";??
??? std::cout << "std::stoi(\"" << str1 << "\") is " << std::stoi(str1) << '\n';//42??
??? std::cout << "std::stoi(\"" << str2 << "\") is " << std::stoi(str2) << '\n';//3??
??? std::cout << "std::stoi(\"" << str3 << "\") is " << std::stoi(str3) << '\n';//31337???
?
??? std::cout << "std::stof(\"" << str1 << "\") is " << std::stof(str1,NULL) << '\n';//42??
??? std::cout << "std::stof(\"" << str2 << "\") is " << std::stof(str2) << '\n';//3.14159??
??? std::cout << "std::stof(\"" << str3 << "\") is " << std::stof(str3) << '\n';//31337???
?
??? std::cout << "std::stod(\"" << str1 << "\") is " << std::stod(str1) << '\n';//42??
??? std::cout << "std::stod(\"" << str2 << "\") is " << std::stod(str2,NULL) << '\n';//3.14159??
??? std::cout << "std::stod(\"" << str3 << "\") is " << std::stod(str3) << '\n';//31337???
?????
??? std::cout << "std::stold(\"" << str1 << "\") is " << std::stold(str1) << '\n';//42??
??? std::cout << "std::stold(\"" << str2 << "\") is " << std::stold(str2) << '\n';//3.14159??
??? std::cout << "std::stold(\"" << str3 << "\") is " << std::stold(str3,NULL) << '\n';//31337???
?????
??? string s1 = "-8246821";//十进制(默认)???
??? string s2 = "-0xffff"; //十六进制??
??? string s3 = "-020";? //八进制??
??? string s4 = "11111110";//是十进制，若要二进制则：stol(s4,NULL,2)??
??? //long? 就是 int的加长版，而不是float的加长版??
??? cout<<"stol("< ??? cout<<"stol("< ?
??? cout<<"stoul("< ??? cout<<"stoul("< ?
??? cout<<"stoll("< ??? cout<<"stoll("< ??? cout<<"stoll("< ??? cout<<"stoll("< ?
??? cout<<"stoull("< ??? cout<<"stoull("< ??? cout<<"stoull("< ??? cout<<"stoull("< }??
//C++11??
//num to string/wstring :to_string(),to_wstring()??
void test7()?
{?
??? long double f=3.1415926;?
??? std::wstring wpi = L"pi is " + std::to_wstring(f);?
??? wstring wperfect = std::to_wstring(_ULonglong(1+2+4+7+14)) + L" is a perfect number";?
??? wcout << wpi << L'\n';//3.14159??
??? wcout << wperfect << L'\n';//28??
?
??? std::string pi = "pi is " + std::to_string(f);?
??? string perfect = std::to_string(long long(1+2+4+7+14)) + " is a perfect number";?
??? cout << pi << endl;//3.14159??
??? cout << perfect << endl;//28??
}?
void Test(char h)?
{?
??? cout<<"press key===="< ??? switch(h)?
??? {??
??? case '0':? test0();break;?
??? case '1':? test1();break;?
??? case '2':? test2();break;?
??? case '3':? test3();break;?
??? case '4':? test4();break;?
??? case '5':? test5();break;??
??? case '6':? test6();break;??
??? case '7':? test7();break;??
??? case 27:?
??? case 'q':exit(0);break;??
??? default:cout<<"default "< ??? }?
}?
void main()?
{?
??? while(1)?
??? {?
??????? Test(getch());?
??? }??
}??
#include
#include
#include
using namespace std;
//1.构造函数
/*
string();
string( size_type length, char ch );
string( const char *str );
string( const char *str, size_type index );
string( string &str, size_type index, size_type length );
string( input_iterator start, input_iterator end );
字符串的构造函数创建一个新字符串，包括:
1.以length为长度的ch的拷贝（即length个ch）
2.以str为初值 (长度任意),
3.以index为索引开始的子串，长度为length,或者
4.以从start |