string

1. stricmp 比较字符串，不区分大小写。#include<string>

http://baike.baidu.com/view/745150.htm

string str1 ,str2 ;

bool bijiao = stricmp( str1 , str2 ) ;

//if ( bijiao < 0 )  ,   str1 < str2;

字符串的大小写转换

1.stl

#include<algorighm>

#include<string>

#include<一种stl容器(set/vector)>

set<string>str ;

transform( str.begin() , str.end() , str.begin() , tolower/toupper ) ;

http://www.cnblogs.com/oomusou/archive/2006/12/10/587749.html

http://blog.youkuaiyun.com/liziyun537/archive/2010/11/04/5988058.aspx

2. tolower

#include<cstype.h>

#include<string>

string str ;

for( int i = 0 ; i < str.size() ; i++ )

{

 str[ i ] = tolower( str[ i ] ) ;

}