152.字符串模板库

string.h

 1 #pragma once
 2 #include <string>
 3 #include <cstdlib>
 4 #include <functional>
 5 using namespace std;
 6 
 7 class outofrange
 8 {
 9 
10 };
11 
12 template <class T>
13 class String
14 {
15 public:
16     //构造
17     String();
18     //析构
19     ~String();
20     //拷贝构造
21     String(const String &str);
22     //字符串构造
23     String(const T *p);
24     //重载=
25     void operator=(const String &str);
26     //重载+=
27     void operator+=(const String &str);
28     //重载+
29     String operator+(const String &str);
30     //重载[]
31     //T operator[] (int id) const;
32     //重载[],返回的是副本
33     T& operator[] (int id) const;
34     //重载宽字符输出
35     template<class T>
36     friend wostream & operator << (wostream &out, const String<T> &str);
37 
38     //重载窄字符输出
39     template<class T>
40     friend ostream & operator << (ostream &out, const String<T> &str);
41 
42     template<class T>
43     friend istream & operator >>(istream &i, const String<T> &str);
44     void replacefirst(const String &oldstr,const String &newstr);
45     /*void replaceall(const String &oldstr, const String &newstr);
46 
47     void findfirst(const String &oldstr, const String &newstr);
48     void findall(const String &oldstr, const String &newstr)
49     void insertfirst(const String &oldstr, const String &newstr)
50     void insertall(const String &oldstr, const String &newstr)
51     void deletefirst(const String &oldstr, const String &newstr)
52     void deleteall(const String &oldstr, const String &newstr)
53     ;*/
54 
55     bool operator ==(const String &str);
56     bool operator !=(const String &str);
57     bool operator >=(const String &str);
58     bool operator <=(const String &str);
59     bool operator >(const String &str);
60     bool operator <(const String &str);
61     T* operator*();
62     
63     //重载->
64     String* operator->();
65     //重载->*
66     String* operator->*(int i);
67     T *getdata();
68     //获取长度
69     int getlength();
70 private:
71     T * pstart;
72     int length;
73     //等号默认自带this指针
74     function<void(void)> fun = [=]() {cout << pstart << endl; };
75 };

string.cpp

  1 #include "String.h"
  2 
  3 template<class T>
  4 inline String<T>::String() :pstart(nullptr), length(0)
  5 {
  6     if (strcmp(typeid(T).name(), "char") == 0)
  7     {
  8 
  9     }
 10     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
 11     {
 12 
 13     }
 14     else
 15     {
 16         cout << "类型不匹配,请认真检查" << endl;;
 17     }
 18 }
 19 
 20 template<class T>
 21 String<T>::~String()
 22 {
 23     if (this->pstart != nullptr)
 24     {
 25         delete[] this->pstart;
 26     }
 27 }
 28 
 29 template<class T>
 30 String<T>::String(const String & str)
 31 {
 32     if (this->pstart != nullptr)
 33     {
 34         delete[] this->pstart;
 35     }
 36     //长度归零
 37     this->length = 0;
 38 
 39     this->length = str.length;
 40     this->pstart = new T[this->length + 1 ];
 41     if (strcmp(typeid(T).name(), "char") == 0)
 42     {
 43         strcpy(reinterpret_cast<char *>(this->pstart), reinterpret_cast<const char *>(str.pstart));
 44     }
 45     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
 46     {
 47         wcscpy(reinterpret_cast<wchar_t *>(this->pstart), reinterpret_cast<const wchar_t *>(str.pstart));
 48     }
 49 }
 50 
 51 template<class T>
 52 String<T>::String(const T * p)
 53 {
 54     if (strcmp(typeid(T).name(), "char") == 0)
 55     {
 56         this->length = strlen(reinterpret_cast<const char*>(p));
 57         this->pstart = new T[this->length + 1 ];
 58         //初始化
 59         strcpy(reinterpret_cast<char*>(this->pstart), reinterpret_cast<const char*>(p));
 60     }
 61     else if(strcmp(typeid(T).name(), "wchar_t") == 0)
 62     {
 63         this->length = wcslen(reinterpret_cast<const wchar_t*>(p));
 64         this->pstart = new T[this->length + 1 ];
 65         wcscpy(reinterpret_cast<wchar_t*>(this->pstart), reinterpret_cast<const wchar_t*>(p));
 66     }
 67     else
 68     {
 69         cout << "类型不匹配,请认真检查" << endl;;
 70     }
 71 }
 72 
 73 template<class T>
 74 void String<T>::operator=(const String & str)
 75 {
 76     if (this->pstart != nullptr)
 77     {
 78         delete[] this->pstart;
 79     }
 80     //长度归零
 81     this->length = 0;
 82 
 83     this->length = str.length;
 84     this->pstart = new T[this->length + 1];
 85     if (strcmp(typeid(T).name(), "char") == 0)
 86     {
 87         strcpy(reinterpret_cast<char *>(this->pstart), reinterpret_cast<const char *>(str.pstart));
 88     }
 89     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
 90     {
 91         wcscpy(reinterpret_cast<wchar_t *>(this->pstart), reinterpret_cast<const wchar_t *>(str.pstart));
 92     }
 93 }
 94 
 95 template<class T>
 96 void String<T>::operator+=(const String & str)
 97 {
 98     this->length += str.length;
 99     T *temp = new T[this->length + 1];
100     if (strcmp(typeid(T).name(), "char") == 0)
101     {
102         strcpy(reinterpret_cast<char*>(temp), reinterpret_cast<const char*>(this->pstart));
103         strcat(reinterpret_cast<char*>(temp), reinterpret_cast<const char*>(str.pstart));
104         delete[] this->pstart;
105         this->pstart = temp;
106     }
107     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
108     {
109         wcscpy(reinterpret_cast<wchar_t*>(temp), reinterpret_cast<const wchar_t*>(this->pstart));
110         wcscat(reinterpret_cast<wchar_t*>(temp), reinterpret_cast<const wchar_t*>(str.pstart));
111         delete[] this->pstart;
112         this->pstart = temp;
113     }
114     else
115     {
116         cout << "类型不匹配,请认真检查" << endl;;
117     }
118 }
119 
120 template<class T>
121 String<T> String<T>::operator+(const String & str)
122 {
123     String<T> temp;
124     temp.length = this->length + str.length;
125     temp.pstart = new T[temp.length+1];
126 
127     if (strcmp(typeid(T).name(), "char") == 0)
128     {
129         strcpy(reinterpret_cast<char*>(temp.pstart), reinterpret_cast<const char*>(this->pstart));
130         strcat(reinterpret_cast<char*>(temp.pstart), reinterpret_cast<const char*>(str.pstart));
131     }
132     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
133     {
134         wcscpy(reinterpret_cast<wchar_t*>(temp.pstart), reinterpret_cast<const wchar_t*>(this->pstart));
135         wcscat(reinterpret_cast<wchar_t*>(temp.pstart), reinterpret_cast<const wchar_t*>(str.pstart));
136     }
137     else
138     {
139         cout << "类型不匹配,请认真检查" << endl;;
140     }
141     return temp;
142 }
143 
144 //template<class T>
145 //T String<T>::operator[](int id) const 
146 //{
147 //    if (id < 0 || id >= this->length)
148 //    {
149 //        //抛出匿名异常
150 //        throw outofrange();
151 //    }
152 //    return this->pstart[id];
153 //}
154 
155 template<class T>
156 T&  String<T>::operator[] (int id) const
157 {
158     if (id < 0 || id >= this->length)
159     {
160         //抛出匿名异常
161         throw outofrange();
162     }
163     return this->pstart[id];
164 }
165 
166 template<class T>
167 void String<T>::replacefirst(const String & oldstr, const String & newstr)
168 {
169     if (strcmp(typeid(T).name(), "char") == 0)
170     {
171         char *p = strstr(reinterpret_cast<char*>(this->pstart), reinterpret_cast<char*>(oldstr.pstart));
172         if (p != nullptr)
173         {
174             int oldlength = strlen(reinterpret_cast<char*>(oldstr.pstart));
175             int newlength = strlen(reinterpret_cast<char*>(newstr.pstart));
176             if (oldlength == newlength)
177             {
178                 memcpy(p, newstr.pstart, newstr.length);
179             }
180             else if (oldlength > newlength)
181             {
182                 memcpy(p, newstr.pstart, newstr.length);
183                 char *pstr = (char *)(p +  strlen(reinterpret_cast<char*>(newstr.pstart)));
184                 int mlength = oldlength - newlength;
185                 while (*(pstr + mlength) != '')
186                 {
187                     *pstr = *(pstr + mlength);
188                     pstr++;
189                 }
190                 *pstr = '';
191             }
192             else
193             {
194                 //分配内存与拷贝
195                 T* ptemp = new T[(this->length + newlength + 1) * sizeof(T)];
196                 memcpy(ptemp, this->pstart, sizeof(T)*(p - reinterpret_cast<char*>(this->pstart)));
197                 memcpy(ptemp + (p - reinterpret_cast<char*>(this->pstart)), newstr.pstart, sizeof(T)*newlength);
198                 memcpy(ptemp + (p - reinterpret_cast<char*>(this->pstart) + newlength), p + oldlength, sizeof(T)*(this->length - oldlength - (p - reinterpret_cast<char*>(this->pstart)) + 1));
199                 this->pstart = ptemp;
200             }
201         }
202     }
203     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
204     {
205         wchar_t *p = wcsstr(reinterpret_cast<wchar_t *>(this->pstart), reinterpret_cast<wchar_t *>(oldstr.pstart));
206         if (p != nullptr)
207         {
208             int oldlength = wcslen(reinterpret_cast<wchar_t*>(oldstr.pstart));
209             int newlength = wcslen(reinterpret_cast<wchar_t*>(newstr.pstart));
210             if (oldlength == newlength)
211             {
212                 memcpy(p, newstr.pstart, newstr.length);
213             }
214             else if (oldlength > newlength)
215             {
216                 memcpy(p, newstr.pstart, newstr.length);
217                 wchar_t *pstr = (wchar_t *)(p + wcslen(reinterpret_cast<wchar_t*>(newstr.pstart)));
218                 int mlength = oldlength - newlength;
219                 while (*(pstr + mlength) != '')
220                 {
221                     *pstr = *(pstr + mlength);
222                     pstr++;
223                 }
224                 *pstr = '';
225             }
226             else
227             {
228                 //分配内存与拷贝
229                 T* ptemp = new T[(this->length + newlength + 1) * sizeof(T)];
230                 memcpy(ptemp, this->pstart, sizeof(T)*(p - reinterpret_cast<wchar_t*>(this->pstart)));
231                 memcpy(ptemp + (p - reinterpret_cast<wchar_t*>(this->pstart)), newstr.pstart, sizeof(T)*newlength);
232                 memcpy(ptemp + (p - reinterpret_cast<wchar_t*>(this->pstart) + newlength), p + oldlength, sizeof(T)*(this->length - oldlength - (p - reinterpret_cast<wchar_t*>(this->pstart)) + 1));
233                 this->pstart = ptemp;
234             }
235         }
236     }
237     else
238     {
239         cout << "类型不匹配,请认真检查" << endl;;
240     }
241 }
242 
243 template<class T>
244 bool String<T>::operator==(const String & str)
245 {
246     if (strcmp(typeid(T).name(), "char") == 0)
247     {
248         return( strcmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) == 0);
249     }
250     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
251     {
252         return (wcscmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) == 0);
253     }
254     else
255     {
256         cout << "类型不匹配,请认真检查" << endl;;
257     }
258 }
259 
260 template<class T>
261 bool String<T>::operator!=(const String & str)
262 {
263     if (strcmp(typeid(T).name(), "char") == 0)
264     {
265         return(strcmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) != 0);
266     }
267     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
268     {
269         return (wcscmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) != 0);
270     }
271     else
272     {
273         cout << "类型不匹配,请认真检查" << endl;;
274     }
275 }
276 
277 template<class T>
278 bool String<T>::operator>=(const String & str)
279 {
280     if (strcmp(typeid(T).name(), "char") == 0)
281     {
282         return(strcmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) >= 0);
283     }
284     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
285     {
286         return (wcscmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) >= 0);
287     }
288     else
289     {
290         cout << "类型不匹配,请认真检查" << endl;;
291     }
292 }
293 
294 template<class T>
295 bool String<T>::operator<=(const String & str)
296 {
297     if (strcmp(typeid(T).name(), "char") == 0)
298     {
299         return(strcmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) <= 0);
300     }
301     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
302     {
303         return (wcscmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) <= 0);
304     }
305     else
306     {
307         cout << "类型不匹配,请认真检查" << endl;;
308     }
309 }
310 
311 template<class T>
312 bool String<T>::operator>(const String & str)
313 {
314     if (strcmp(typeid(T).name(), "char") == 0)
315     {
316         return(strcmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) > 0);
317     }
318     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
319     {
320         return (wcscmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) > 0);
321     }
322     else
323     {
324         cout << "类型不匹配,请认真检查" << endl;;
325     }
326 }
327 
328 template<class T>
329 bool String<T>::operator<(const String & str)
330 {
331     if (strcmp(typeid(T).name(), "char") == 0)
332     {
333         return(strcmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) < 0);
334     }
335     else if (strcmp(typeid(T).name(), "wchar_t") == 0)
336     {
337         return (wcscmp(reinterpret_cast<char *>(this->pstart), reinterpret_cast<char *>(str.pstart)) < 0);
338     }
339     else
340     {
341         cout << "类型不匹配,请认真检查" << endl;;
342     }
343 }
344 
345 template<class T>
346 T * String<T>::operator*()
347 {
348     return this->pstart;
349 }
350 
351 template<class T>
352 String<T> * String<T>::operator->()
353 {
354     return this;
355 }
356 
357 template<class T>
358 String<T> * String<T>::operator->*(int i)
359 {
360     return this;
361 }
362 
363 template<class T>
364 T * String<T>::getdata()
365 {
366     return this->pstart;
367 }
368 
369 template<class T>
370 int String<T>::getlength()
371 {
372     return this->length;
373 }
374 
375 template<class T>
376 wostream & operator<<(wostream & out, const String<T>& str)
377 {
378         out << str.pstart << endl;
379         return out;    
380 }
381 
382 template<class T>
383 ostream & operator<<(ostream & out, const String<T>& str)
384 {
385     out << str.pstart;
386     return out;
387 }
388 
389 template<class T>
390 istream & operator>>(istream & i, const String<T> & str)
391 {
392     // TODO: 在此处插入 return 语句
393     i >> str.pstart;
394     return i;
395 }

test.cpp

 1 #define _CRT_SECURE_NO_WARNINGS
 2 
 3 #include <iostream>
 4 #include <cstdlib>
 5 #include "String.h"
 6 #include "String.cpp"
 7 #include <locale>
 8 using namespace std;
 9  
10 void main()
11 {
12     ////要输出宽字符,要加上这句话
13     //wcout.imbue(locale("", LC_CTYPE));
14 
15     //String<char> str("hello");
16 
17     //cout << str << endl;
18     //String<wchar_t> str2(L"你好");
19     //wcout << str2;
20 
21     //String<char> str3(str);
22     //cout << str3 << endl;
23 
24     //str += str3;
25     //cout << str << endl;
26 
27     //String<char> str4 = str3 + str;
28     //cout << str4 << endl;
29 
30     //String<wchar_t> str5(L"吗");
31     //str2 += str5;
32     //wcout << str2 << endl;
33 
34     String<wchar_t> str(L"hello");
35 
36     /*cout << *str << endl;
37 
38     cout << str->getdata() << endl;
39 
40     cout << (str->*3)->getdata() << endl;*/
41     str.replacefirst(L"he", L"tuu");
42     wcout << str << endl;
43     cin.get();
44 }