String基本字符系列容器

1、

/*创建s 空字符串*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){string s;cout<<s.length()<<endl;return 0;}

 

2、基本字符系列容器给string对象赋值

/*直接给字符串对象赋值*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){    string s;    s="hello,C++STL!";    cout<<s<<endl;    return 0;}

3、

/*把字符指针赋给字符串对象*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){string s;char ss[100];scanf("%s",&ss);s=ss;cout<<s<<endl;return 0;}

 

/*String基本字符系列容器 从string对象尾部添加字符使用“+”操作符*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){string s;s=s+"a";s=s+"b";s=s+"c";cout<<s<<endl;return 0;}/*String基本字符系列容器 从string对象尾部添加字符串使用“+”操作符*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(int argc, char* argv[]){string s;s=s+"abc";s=s+"123";cout<<s<<endl;return 0;}/*使用append()方法*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(int argc, char* argv[]){string s;s.append("abc");s.append("123");cout<<s<<endl;return 0;}

4、基本字符系列容器给string对象插入字符

/*使用insert()方法把一个字符插入到迭代器位置之前*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){    string s;    s="1234567";    string::iterator it=s.begin();    s.insert(it+1,'p');    cout<<s<<endl;    return 0;}

 

5、基本字符系列容器访问string对象的元素

 

/*使用下标方式随机访问 从0开始计数*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){    string s;    s="abc1234567";    cout<<s[0]<<endl;    cout<<s[0]-'a'<<endl;    return 0;}

 

6、基本字符系列容器删除string对象的元素

/*清空一个字符串 则赋给它一个空串使用erase()删除迭代器所指的那个元素或者一个区间里的所有元素*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){    string s;    s="abc1234567";    string::iterator it=s.begin();    s.erase(it+3);    cout<<s<<endl;    s.erase(it,it+4);    cout<<s<<endl;    return 0;}

 

7、基本字符系列容器返回string对象的长度

/*使用length()返回其长度 使用empty()判断字符串是否为空*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){string s;s="abc1234567";cout<<s.length()<<endl;s="";cout<<s.empty()<<endl;return 0;}

 

8、基本字符系列容器替换string对象的字符

/*使用replace()替换字符串中的字符*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){string s;s="abc1234567";s.replace(3,3,"good");/*replace(a,b,c) a代表下表位置，b代表连续的数量，c代表要替换成的字符（串）*/cout<<s<<endl;return 0;}

 

9、基本字符系列容器搜索string对象中的元素或子串

/*使用find()方法可查找字符串中的第一个字符元素或者子串 若查到返回其下标值 否则返回4294967295*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){string s;s="cat dog cat";cout<<s.find('c')<<endl;cout<<s.find("c")<<endl;cout<<s.find("cat")<<endl;cout<<s.find("dog")<<endl;cout<<s.find("dogc")<<endl;return 0;}

 

10、String基本字符系列容器

/*使用reverse()反向排列string对象迭代器所指的一段区间的元素*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){    string s;    s="0123456789";    reverse(s.begin(),s.end());    cout<<s<<endl;    return 0;}

 

/*类似字符串数组*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){    vector<string> v;    v.push_back("Jack");    v.push_back("Mick");    v.push_back("Tom");    cout<<v[0]<<endl;    cout<<v[1]<<endl;    cout<<v[2]<<endl;    cout<<v[0][0]<<endl;    cout<<"****"<<v[2][2]<<"******"<<endl;    cout<<v[2].length()<<endl;    return 0;}

11、基本字符系列容器 string类型的数字化处理

/*将读入的数据当成字符串来处理 可以避免用取余的方法 将读入的数据的每位分离开来*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){string s="123456789";int sum=0;for(int i=0;i<s.length();i++){if(s[i]=='0') sum+=0;else if(s[i]=='1') sum+=1;else if(s[i]=='2') sum+=2;else if(s[i]=='3') sum+=3;else if(s[i]=='4') sum+=4;else if(s[i]=='5') sum+=5;else if(s[i]=='6') sum+=6;else if(s[i]=='7') sum+=7;else if(s[i]=='8') sum+=8;else if(s[i]=='9') sum+=9;}cout<<sum<<endl;return 0;}

12、对象与sscanf函数

/*sscanf函数可以将字符串以你需要的方式分离出子串 甚至是数字*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){string s1,s2,s3;char sa[100],sb[100],sc[100];sscanf("abc 123 pc","%s %s %s",sa,sb,sc);s1=sa;s2=sb;s3=sc;cout<<s1<<" "<<s2<<" "<<s3<<endl;int a,b,c,d;sscanf("1 2,3,4","%d %d,%d,%d",&a,&b,&c,&d);cout<<a<<" "<<b<<" "<<c<<" "<<d<<endl;return 0;}

 

13、对象与数值的相互转换

/*string对象与数值的相互转换*/#include<iostream>#include<string.h>#include<stdio.h>#include<ctype.h>#include<algorithm>#include<stack>#include<queue>#include<math.h>using namespace std;int main(){    char bb[10];    string b;    sscanf("1991","%s",&bb);    /*sscanf函数, 可以将字符串转换成数字    sscanf(a,"%d",&b)a代表要输入的字符；b代表将字符存放的位置,注意&*/    b=bb;    cout<<b<<endl;    sprintf(bb,"%d",1991);//sprintf函数, 可以将数字转换成字符串    b=bb;    cout<<b<<endl;    return 0;}