CStrFun 

 1 #ifndef _STR_FUN_H_030802
 2 #define _STR_FUN_H_030802
 3 
 4 #include <string>
 5 #include <sstream>
 6 #include <iostream>
 7 #include <algorithm>
 8 
 9 using namespace std;
10 
11 class CStrFun
12 {
13 public:
14     CStrFun();
15     virtual ~CStrFun();
16     //把类中的函数都定义成静态函数，这样相当于在编译时就分配了空间，这样不需要实体对象也可以调用泪中的函数了。
17     static void Str2Lower(string &sSource, int nLen);
18     static string itos(long long i)
19     {
20         stringstream s;
21         s << i;
22         return s.str();
23     }
24 
25     /* Locate a substring ignoring case
26      * The  function  returns a value equal or lager than zero,
27          * or -1 if the substring is not found.
28      */
29 
30     static string::size_type FindCase(string haystack, string needle);
31     static string::size_type FindCaseFrom(string haystack, string needle, int From);
32 
33     static void ReplaceStr(string &str, string srstr, string dsstr);
34     static void EraseStr(string &str, string substr);
35 };
36 
37 #endif    // end _STR_FUN_H_030802
38 
39 /*
40 ostringstream oss<<Dea<<'.'<<pre();
41 
42 oss.str();
43 */

 

 

 1 #include "StrFun.h"
 2 
 3 CStrFun::CStrFun() {
 4 
 5 }
 6 
 7 CStrFun::~CStrFun() {
 8 
 9 }
10 
11 void CStrFun::Str2Lower(string& str, int nLen) //将大写字母改写成小写字母
12         {
13     char distance = 'A' - 'a';
14 
15     for (int i = 0; i < nLen; i++)
16         if (str[i] >= 'A' && str[i] <= 'Z')
17             str[i] -= distance;
18 }
19 
20 bool _nocase_compare(char c1, char c2) //不区分大小写的比较
21         {
22     return toupper(c1) == toupper(c2);
23 }
24 
25 string::size_type CStrFun::FindCase(string haystack, string needle) //在haystack中找第一个匹配needle的位置
26         {
27     if (haystack.empty())
28         return string::npos;
29     if (needle.empty())
30         return string::npos;
31 
32     string::iterator pos;
33     pos = search(haystack.begin(), haystack.end(), needle.begin(), needle.end(),
34             _nocase_compare);
35 
36     if (pos == haystack.end()) {
37         return string::npos;
38     } else {
39         return (pos - haystack.begin());
40     }
41 }
42 
43 string::size_type CStrFun::FindCaseFrom(string haystack, string needle,
44         int nFrom) //在haystack中的第n个位置找第一个匹配needle的位置
45         {
46     //assert( haystack.empty() == false );
47     //assert( needle.empty() == false );
48     if (haystack.empty())
49         return string::npos;
50     if (needle.empty())
51         return string::npos;
52 
53     string::iterator pos;
54     pos = search(haystack.begin() + nFrom, haystack.end(), needle.begin(),
55             needle.end(), _nocase_compare);
56 
57     if (pos == haystack.end()) {
58         return string::npos;
59     } else {
60         return (pos - haystack.begin());
61     }
62 }
63 
64 void CStrFun::EraseStr(string &str, string substr) //在str中删除所有出现的substr
65         {
66     if (str.size() == 0 || substr.size() == 0)
67         return;
68 
69     string::size_type idx = 0;
70     string::size_type sub_length = substr.length();
71     idx = str.find(substr, idx);
72     while (idx != string::npos) {
73         str.erase(idx, sub_length);
74         idx = str.find(substr, idx);
75     }
76 }
77 
78 void CStrFun::ReplaceStr(string&str, string srstr, string dsstr) //将str中的字串替换成dsstr
79         {
80     if (str.size() == 0 || srstr.size() == 0)
81         return;
82 
83     string::size_type idx = 0;
84     string::size_type sub_length = srstr.length();
85     idx = str.find(srstr, idx);
86     while (idx != string::npos) {
87         str.replace(idx, sub_length, dsstr);
88 
89         if (idx + dsstr.size() > str.size())
90             break;
91 
92         idx = str.find(srstr, idx + dsstr.size());
93     }
94 }

posted on 2012-07-01 15:58  kakamilan  阅读(357)  评论(0)    收藏  举报

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