istringstream字符串流，实现类似字符串截取的功能，字符串流中的put，str()将流转换成为字符串string



1. istringstream字符串流

#include
<iostream>

#include
<sstream>

#include
<string>

using
namespace
std;

struct
MyStruct

{

string
str1,
str2,
str3;

double
db;

int
num;

char
ch;

};

void
main()

{

string 
mystring("china 
google microsoft 12.9 123 A");

MyStruct
struct1;

istringstream
input(mystring);//创建一个字符串扫描流

input >>
struct1.str1
>> struct1.str2
>> struct1.str3
>> struct1.db
>> struct1.num
>> struct1.ch;

cout <<
struct1.str1
<< endl;

cout <<
struct1.str2
<< endl;

cout <<
struct1.str3
<< endl;

cout <<
struct1.db
<< endl;

cout <<
struct1.num
<< endl;

cout <<
struct1.ch
<< endl;

cin.get();

}

2.实现类似字符串截取的功能

#include
<iostream>

#include
<sstream>

#include
<string>

using
namespace
std;

//实现类似字符串截取的功能

void
main()

{

char
mystring[50] =
"china#123#A";

for (char
*p =
mystring; *p
!= ‘\0‘;
p++)

{

if (*p
== ‘#‘)

{

*p =
‘ ‘;

}

}

istringstream
input(mystring);//创建一个字符串扫描流

string
str;

int
num;

char
ch;

input >>
str >>
num >>
ch;

cout <<
str <<
endl;

cout <<
num <<
endl;

cout <<
ch <<
endl;

cin.get();

}

运行结果：

3.实现类似字符串截取的功能

#include
<iostream>

#include
<sstream>

#include
<string>

using
namespace
std;

//实现类似字符串截取的功能

void
main()

{

ostringstream 
MYOUT;

char
str[100] = { 0 };

//ostringstream MYOUT(str,sizeof(str));

char
str1[50] =
"a1234567b";

MYOUT <<
"a1234b" <<
" " << 123<<
""<< 234.89 <<
" " <<
‘h‘ <<
" " <<
str1 <<
endl;

cout <<
MYOUT.str();

//cout <<str;

cin.get();

}

运行结果如下：

4.字符串流中的put

#define
_CRT_SECURE_NO_WARNINGS

#include
<iostream>

#include
<sstream>

#include
<string>

#include
<stdlib.h>

using
namespace
std;

void
main()

{

stringstream
mystr;//字符串进行输入

mystr.put(‘X‘).put(‘Y‘);//连个字符输入

mystr <<
"ZXCV";//字符串输入

cout <<
mystr.str();

string
str =
mystr.str();//定义字符串接受值

char
ch;   
//从字符串内部读取一个字符

mystr >>
ch;

cout <<
"\n";

cout.put(ch);

cout <<
"\n";

cout <<
mystr.str();

std::cin.get();

system("pause");

}

运行结果

5.str()将流转换成为字符串string

#define
_CRT_SECURE_NO_WARNINGS

#include
<iostream>

#include
<sstream>

#include
<string>

#include
<stdlib.h>

using
namespace
std;

void
main()

{

stringstream
mystr;//sprintf功能

char
cmd1[30] = { 0 };

char
cmd2[30] = { 0 };

cin.getline(cmd1,
30).getline(cmd2,
30);//输入两个字符串

mystr <<
cmd1 <<
"&" <<
cmd2;//字符打印

string
str =
mystr.str();//定义字符串接受值

system(str.c_str());

char
cstr[50] = { 0 };//默认的字符串

strcpy(cstr,
str.c_str());

cout <<
cstr <<
endl;

for (char
*p =
cstr; *p
!= ‘\0‘;
p++)

{

if (*p
== ‘&‘)

{

*p =
‘ ‘;

}

}

char
newcmd1[30] = { 0 };

char
newcmd2[30] = { 0 };

stringstream 
newstr(cstr);//sscanf的功能

newstr >>
newcmd1 >>
newcmd2;

cout <<
newcmd1 <<
"\n" <<
newcmd2 <<
endl;

system("pause");

}