C++中int型与string型互相转换

像是C#,java等高级语言中,int转String类型都是很简单的,但是C++中比较麻烦：

int 转换string

string int2str( int num)

{

if (num == 0 )

return " 0 " ;

string str = "" ;

int num_ = num > 0 num : - 1 * num;

while (num_)

{

str = ( char )(num_ % 10 + 48 ) + str;

num_ /= 10 ;

}

if (num < 0 )

str = " - " + str;

return str;

}

string 转换int

int str2int( string str)

{

int i,len = str.size(),num = 0 ;

i = 0 ;

if (str[ 0 ] == ' - ' )

i = 1 ;

while (i < len)

{

num = num * 10 + ( int )(str[i] - ' 0 ' );

i ++ ;

}

if (str[ 0 ] == ' - ' )

num *= - 1 ;

return num;

}