C++ 字符串 3-- 18.11~12.string型字符串对象的赋值

#include <iostream>
#include <string>
using namespace std;
/*---------------------------------
     18-03 18.11~12.string型字符串对象的赋值
---------------------------------*/
int main()
{
char ch1[]="give me";
char ch2[]="a cup";
cout<<"change before....:"<<endl;
cout<<ch1<<endl;
cout<<ch2<<endl;
strcpy(ch1,ch2);
cout<<"change after....:"<<endl;
cout<<ch1<<endl;
cout<<ch2<<endl;


cout<<"------------------:"<<endl;
string str1="give me";
string str2="a cup";
cout<<"change before....:"<<endl;
cout<<str1<<endl<<str2<<endl;
str1=str2;
cout<<"change after....:"<<endl;
cout<<str1<<endl<<str2<<endl;


cout<<"------------------:"<<endl;
str1="give me";
str2="a cup";
cout<<"change before....:"<<endl;
cout<<str1<<endl<<str2<<endl;
str1.assign(str2,3,2); //将str2中脚标为3开始的连续两个字符赋值给str1
cout<<"change after....:"<<endl;
cout<<str1<<endl<<str2<<endl;


return 0;

}

运行结果：

change before....:
give me
a cup
change after....:
a cup
a cup
------------------:
change before....:
give me
a cup
change after....:
a cup
a cup
------------------:
change before....:
give me
a cup
change after....:
up
a cup
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