![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/08\/20250816000600-689fcb68794a2.jpg\")
<\/p>\n\u672c\u6587\u5b9e\u73b0\u4e86\u4e00\u4e2a\u7b80\u6613\u7684string\u7c7b，\u4e3b\u8981\u5305\u542b\u4ee5\u4e0b\u529f\u80fd：<\/p>\n
1. \u9ed8\u8ba4\u6210\u5458\u51fd\u6570：\u6784\u9020\u51fd\u6570（\u9ed8\u8ba4\/\u53c2\u6570\u5316）\u3001\u62f7\u8d1d\u6784\u9020\u3001\u8d4b\u503c\u91cd\u8f7d\u548c\u6790\u6784\u51fd\u6570，\u91c7\u7528\u6df1\u62f7\u8d1d\u907f\u514d\u5185\u5b58\u95ee\u9898；<\/p>\n
2. \u8fed\u4ee3\u5668\u652f\u6301：\u901a\u8fc7char*\u5b9e\u73b0begin()\/end()\u8fed\u4ee3\u5668；<\/p>\n
3. \u5bb9\u91cf\u64cd\u4f5c：size()\/capacity()\u83b7\u53d6\u5927\u5c0f\u5bb9\u91cf，reserve()\/resize()\u8c03\u6574\u7a7a\u95f4；<\/p>\n
4. \u5b57\u7b26\u4e32\u4fee\u6539：push_back()\u3001append()\u3001insert()\u3001erase()\u7b49\u64cd\u4f5c；<\/p>\n
5. \u8bbf\u95ee\u64cd\u4f5c：\u91cd\u8f7doperator[]\u548cc_str()\u65b9\u6cd5；<\/p>\n
6. \u5b9e\u7528\u529f\u80fd：find()\u67e5\u627e\u3001substr()\u5b50\u4e32；<\/p>\n
7. \u8fd0\u7b97\u7b26\u91cd\u8f7d：\u5173\u7cfb\u8fd0\u7b97\u7b26\u3001\u6d41\u64cd\u4f5c\u7b26<<\u548c>>\u3002\u7c7b\u5185\u90e8\u4f7f\u7528\u52a8\u6001\u5206\u914d\u7684char\u6570\u7ec4\u5b58\u50a8\u5b57\u7b26\u4e32，\u901a\u8fc7_size\u548c_capacity\u7ba1\u7406\u7a7a\u95f4\u3002\u5b9e\u73b0\u65f6\u7279\u522b\u6ce8\u610f\u4e86\u6df1\u62f7\u8d1d\u3001\u8fb9\u754c\u68c0\u67e5\u548c\u5185\u5b58\u7ba1\u7406，\u57fa\u672c\u6a21\u62df\u4e86\u6807\u51c6string\u7c7b\u7684\u6838\u5fc3\u529f\u80fd\u3002<\/p>\n
\u76ee\u5f55<\/p>\n
\u00a0\u6458\u8981：<\/p>\n
\u5b9e\u73b0\u6846\u67b6<\/p>\n
\u4e00\u3001\u9ed8\u8ba4\u6210\u5458\u51fd\u6570<\/p>\n
1.\u9ed8\u8ba4\u6784\u9020\u51fd\u6570<\/p>\n
2.\u6784\u9020\u51fd\u6570<\/p>\n
3.\u62f7\u8d1d\u6784\u9020\u51fd\u6570(\u91cd\u70b9)<\/p>\n
4.\u8d4b\u503c\u8fd0\u7b97\u7b26\u91cd\u8f7d\u51fd\u6570<\/p>\n
5.\u6790\u6784\u51fd\u6570<\/p>\n
\u4e8c\u3001\u8fed\u4ee3\u5668\u76f8\u5173\u51fd\u6570<\/p>\n
begin\u548cend<\/p>\n
\u4e09\u3001\u5bb9\u91cf\u548c\u5927\u5c0f\u76f8\u5173\u51fd\u6570<\/p>\n
size\u548ccapacity<\/p>\n
reserve\u548cresize<\/p>\n
\u56db\u3001\u4e0e\u4fee\u6539\u5b57\u7b26\u4e32\u76f8\u5173\u7684\u51fd\u6570<\/p>\n
push_back<\/p>\n
append<\/p>\n
operator+=<\/p>\n
insert\u00a0<\/p>\n
erase<\/p>\n
clear<\/p>\n
\u4e94\u3001\u8bbf\u95ee\u5b57\u7b26\u4e32\u76f8\u5173\u51fd\u6570<\/p>\n
operator[ ]<\/p>\n
c_str<\/p>\n
\u5c0f\u77e5\u8bc6\u70b9- npos<\/p>\n
find\u51fd\u6570<\/p>\n
substr\u51fd\u6570<\/p>\n
\u516d\u3001\u5173\u7cfb\u8fd0\u7b97\u7b26\u91cd\u8f7d\u51fd\u6570<\/p>\n
>\u3001>=\u3001<\u3001<=\u3001==\u3001!=<\/p>\n
>>\u548c<<\u8fd0\u7b97\u7b26\u7684\u91cd\u8f7d<\/p>\n
#include<iostream>
\n#include<assert.h>
\nusing namespace std;<\/p>\n
namespace lzg
\n{
\nclass string
\n{
\npublic:
\n\/\/typedef char* iterator;
\nusing iterator = char*;
\nusing const_iterator = const char*;<\/p>\n
\/\/\u4e00\u3001\u9ed8\u8ba4\u6210\u5458\u51fd\u6570
\nstring(const char* str = ""); \/\/\u9ed8\u8ba4\u6784\u9020
\nstring(const string& s); \/\/\u62f7\u8d1d\u6784\u9020
\nstring& operator=(const string& s); \/\/\u8d4b\u503c\u91cd\u8f7d
\n~string(); \/\/\u6790\u6784\u51fd\u6570<\/p>\n
\/\/\u4e8c\u3001\u8fed\u4ee3\u5668\u76f8\u5173\u51fd\u6570
\niterator begin()
\n{
\nreturn _str;
\n}
\niterator end()
\n{
\nreturn _str + _size;
\n}
\nconst_iterator begin() const
\n{
\nreturn _str;
\n}
\nconst_iterator end() const
\n{
\nreturn _str + _size;
\n}<\/p>\n
\/\/\u4e09\u3001\u5bb9\u91cf\u548c\u5927\u5c0f\u76f8\u5173\u51fd\u6570
\nvoid reserve(size_t n);
\nsize_t size() const
\n{
\nreturn _size;
\n}
\nsize_t capacity() const
\n{
\nreturn _capacity;
\n}
\nvoid resize(size_t n, char ch = '\\\\0');<\/p>\n
\/\/\u56db\u3001\u4e0e\u4fee\u6539\u5b57\u7b26\u4e32\u76f8\u5173\u7684\u51fd\u6570
\nvoid push_back(char ch);
\nvoid append(const char* str);
\nstring& operator+=(char ch);
\nstring& operator+=(const char* str);
\nvoid insert(size_t pos, char ch);
\nvoid insert(size_t pos, const char* str);
\nvoid erase(size_t pos, size_t len = npos);
\nvoid clear()
\n{
\n_str[0] = '\\\\0';
\n_size = 0;
\n}<\/p>\n
\/\/\u4e94\u3001\u8bbf\u95ee\u5b57\u7b26\u4e32\u76f8\u5173\u51fd\u6570
\nchar& operator[](size_t i)
\n{
\nassert(i < _size);<\/p>\n
return _str[i];
\n}<\/p>\n
const char& operator[](size_t i) const
\n{
\nassert(i < _size);<\/p>\n
return _str[i];
\n}
\nconst char* c_str() const
\n{
\nreturn _str;
\n}
\nsize_t find(char ch, size_t pos = 0);
\nsize_t find(const char* str, size_t pos = 0);
\nstring substr(size_t pos, size_t len = npos);<\/p>\n
private:
\nchar* _str = nullptr;
\nsize_t _size = 0;
\nsize_t _capacity = 0;<\/p>\n
public:
\nstatic const size_t npos;
\n};
\n\/\/\u516d\u3001\u5173\u7cfb\u8fd0\u7b97\u7b26\u91cd\u8f7d\u51fd\u6570
\nbool operator== (const string& lhs, const string& rhs);
\nbool operator!= (const string& lhs, const string& rhs);
\nbool operator> (const string& lhs, const string& rhs);
\nbool operator< (const string& lhs, const string& rhs);
\nbool operator>= (const string& lhs, const string& rhs);
\nbool operator<= (const string& lhs, const string& rhs);<\/p>\n
ostream& operator<<(ostream& os, const string& str);
\nistream& operator>>(istream& is, string& str);
\n} <\/p>\n
string()
\n:_str(new char[1] {'\\\\0'}),
\n_size(0),
\n_capacity(0)
\n{} <\/p>\n
\u4e3a_str\u5f00\u8f9f1\u5b57\u8282\u7a7a\u95f4\u6765\u5b58\u653e'\\\\0'_capacity\u4e0d\u8bb0\u5f55\\\\0\u7684\u5927\u5c0f，\u8fd9\u6837\u8c03\u7528c_str()\u5c31\u4e0d\u4f1a\u62a5\u9519<\/p>\n
string(const char* str)
\n:_size(strlen(str))
\n{
\n_capacity = _size;
\n_str = new char[_size + 1];
\nstrcpy(_str, str);
\n} <\/p>\n
\u6ce8\u610f\u5728private\u4e2d\u7684\u58f0\u660e\u987a\u5e8f，\u8fd9\u91cc\u521d\u59cb\u5316\u5217\u8868\u53ea\u8d70_size(\u5927\u5c0f\u4e3astr\u7684\u957f\u5ea6)，\u8ba9_str\u548c_capacity\u5728\u51fd\u6570\u4f53\u5185\u521d\u59cb\u5316(\u8fd9\u6837\u4fdd\u8bc1\u4e86\u4e0d\u4f1a\u51fa\u9519，\u6bd4\u5982\u4e09\u8005\u90fd\u5728\u521d\u59cb\u5316\u5217\u8868\u7684\u8bdd，\u4f1a\u5148\u521d\u59cb\u5316_str\u8fd9\u6837\u6709\u98ce\u9669)，\u540c\u6837\u7684，_str\u5f00\u8f9f\u7a7a\u95f4\u65f6，\u4e3a'\\\\0'\u591a\u5f00\u8f9f1\u5b57\u8282<\/p>\n
\u6784\u9020\u51fd\u6570\u6709\u4e00\u4e2a\u9ed8\u8ba4\u6784\u9020\u5c31\u884c\u4e86，\u51991\u4e2a\u5c31\u884c，\u628a1\u6ce8\u91ca\u6389，\u5e76\u628a2\u6539\u4e3a\u5168\u7f3a\u7701<\/p>\n
string(const char* str="")\/\/\u4e0d\u8981\u5199\u6210" "\u8fd9\u662f\u975e\u7a7a
\n:_size(strlen(str))
\n{
\n_capacity = _size;
\n_str = new char[_size + 1];
\nstrcpy(_str, str);
\n} <\/p>\n
\u5728\u6a21\u62df\u5b9e\u73b0\u62f7\u8d1d\u6784\u9020\u51fd\u6570\u524d，\u6211\u4eec\u5e94\u8be5\u9996\u5148\u4e86\u89e3\u6df1\u6d45\u62f7\u8d1d：<\/p>\n
\u6211\u4eec\u4e0d\u5199\u62f7\u8d1d\u6784\u9020，\u7f16\u8bd1\u5668\u9ed8\u8ba4\u751f\u6210\u7684\u62f7\u8d1d\u6784\u9020\u662f\u503c\u62f7\u8d1d\u4e5f\u53eb\u6d45\u62f7\u8d1d<\/p>\n
\u6d45\u62f7\u8d1d：\u62f7\u8d1d\u51fa\u6765\u7684\u76ee\u6807\u5bf9\u8c61\u7684\u6307\u9488\u548c\u6e90\u5bf9\u8c61\u7684\u6307\u9488\u6307\u5411\u7684\u5185\u5b58\u7a7a\u95f4\u662f\u540c\u4e00\u5757\u7a7a\u95f4\u3002\u5176\u4e2d\u4e00\u4e2a\u5bf9\u8c61\u7684\u6539\u52a8\u4f1a\u5bf9\u53e6\u4e00\u4e2a\u5bf9\u8c61\u9020\u6210\u5f71\u54cd\u3002 \u6df1\u62f7\u8d1d：\u6df1\u62f7\u8d1d\u662f\u6307\u6e90\u5bf9\u8c61\u4e0e\u62f7\u8d1d\u5bf9\u8c61\u4e92\u76f8\u72ec\u7acb\u3002\u5176\u4e2d\u4efb\u4f55\u4e00\u4e2a\u5bf9\u8c61\u7684\u6539\u52a8\u4e0d\u4f1a\u5bf9\u53e6\u5916\u4e00\u4e2a\u5bf9\u8c61\u9020\u6210\u5f71\u54cd\u3002<\/p>\n
\u5f88\u660e\u663e，\u6211\u4eec\u5e76\u4e0d\u5e0c\u671b\u62f7\u8d1d\u51fa\u6765\u7684\u4e24\u4e2a\u5bf9\u8c61\u4e4b\u95f4\u5b58\u5728\u76f8\u4e92\u5f71\u54cd，\u56e0\u6b64，\u6211\u4eec\u8fd9\u91cc\u9700\u8981\u7528\u5230\u6df1\u62f7\u8d1d\u3002<\/p>\n
\/\/s2(s1) s1
\nstring(const string& s)
\n{
\n_str = new char[s._capacity + 1];
\nstrcpy(_str, s._str);
\n_capacity = s._capacity;
\n_size = s._size;<\/p>\n
} <\/p>\n
\u4e0e\u62f7\u8d1d\u6784\u9020\u51fd\u6570\u7c7b\u4f3c，\u8d4b\u503c\u8fd0\u7b97\u7b26\u91cd\u8f7d\u51fd\u6570\u7684\u6a21\u62df\u5b9e\u73b0\u4e5f\u6d89\u53ca\u6df1\u6d45\u62f7\u8d1d\u95ee\u9898，\u6211\u4eec\u540c\u6837\u9700\u8981\u91c7\u7528\u6df1\u62f7\u8d1d<\/p>\n
\u518d\u5f3a\u8c03\u4e00\u4e0b\u8d4b\u503c\u548c\u62f7\u8d1d\u7684\u533a\u522b，\u8d4b\u503c\u662f\u4e24\u4e2a\u5df2\u521b\u5efa\u7684\u5bf9\u8c61\u4e4b\u95f4\u5b8c\u6210\u8d4b\u503c\u64cd\u4f5c，\u62f7\u8d1d\u662f\u6307\u4e00\u4e2a\u5df2\u521b\u5efa\u7684\u5bf9\u8c61\u8c03\u7528\u62f7\u8d1d\u6784\u9020\u751f\u6210\u4e00\u4e2a\u65b0\u7684\u5bf9\u8c61<\/p>\n
\/\/ s1 = s3 s3
\nstring& operator=(const string& s)
\n{
\nif (this != &s)\/\/\u907f\u514d\u81ea\u5df1\u7ed9\u81ea\u5df1\u8d4b\u503c
\n{
\ndelete[] _str; \/\/\u91ca\u653e\u6389s1\u7684\u65e7\u7a7a\u95f4，\u5f00\u8f9f\u4e00\u4e2a\u548cs3\u5bb9\u91cf\u7684\u65b0\u7a7a\u95f4
\n_str = new char[s._capacity + 1];
\nstrcpy(_str, s._str);
\n_size = s._size;
\n_capacity = s._capacity;
\n}<\/p>\n
return *this;
\n} <\/p>\n
~string()
\n{
\ndelete[] _str;
\n_str = nullptr;
\n_size = _capacity = 0;
\n} <\/p>\n
string\u7c7b\u4e2d\u7684\u8fed\u4ee3\u5668\u5b9e\u9645\u4e0a\u5c31\u662f\u5b57\u7b26\u6307\u9488，\u53ea\u662f\u7ed9\u5b57\u7b26\u6307\u9488\u8d77\u4e86\u4e00\u4e2a\u522b\u540d\u53ebiterator\u800c\u5df2\u3002<\/p>\n
typedef char* iterator;<\/p>\n
typedef const char* const_iterator;<\/p>\n
iterator begin()
\n{
\nreturn _str; \/\/\u8fd4\u56de\u5b57\u7b26\u4e32\u4e2d\u7b2c\u4e00\u4e2a\u5b57\u7b26\u7684\u5730\u5740
\n}<\/p>\n
const_iterator begin()const
\n{
\nreturn _str; \/\/\u8fd4\u56de\u5b57\u7b26\u4e32\u4e2d\u7b2c\u4e00\u4e2a\u5b57\u7b26\u7684const\u5730\u5740
\n}<\/p>\n
iterator end()
\n{
\nreturn _str + _size; \/\/\u8fd4\u56de\u5b57\u7b26\u4e32\u4e2d\u6700\u540e\u4e00\u4e2a\u5b57\u7b26\u7684\u540e\u4e00\u4e2a\u5b57\u7b26\u7684\u5730\u5740
\n}<\/p>\n
const_iterator end()const
\n{
\nreturn _str + _size; \/\/\u8fd4\u56de\u5b57\u7b26\u4e32\u4e2d\u6700\u540e\u4e00\u4e2a\u5b57\u7b26\u7684\u540e\u4e00\u4e2a\u5b57\u7b26\u7684const\u5730\u5740
\n}<\/p>\n
\u5176\u5b9e\u8303\u56f4for\u7684\u5e95\u5c42\u5c31\u662f\u8c03\u7528\u4e86begin()\u548cend()\u8fed\u4ee3\u5668，\u5f53\u4f60\u6a21\u62df\u5b9e\u73b0\u4e86\u8fed\u4ee3\u5668，\u8303\u56f4for\u81ea\u7136\u5c31\u80fd\u4f7f\u7528<\/p>\n
string s("hello world!!!");
\n\/\/\u7f16\u8bd1\u5668\u5c06\u5176\u66ff\u6362\u4e3a\u8fed\u4ee3\u5668\u5f62\u5f0f
\nfor (auto e : s)
\n{
\ncout << e << " ";
\n}
\ncout << endl;<\/p>\n
\u6ce8：\u81ea\u5df1\u5199\u7684begin()\u548cend()\u51fd\u6570\u540d\u5fc5\u987b\u662f\u8fd9\u6837\u7684，\u4e0d\u80fd\u6709\u4efb\u4f55\u5927\u5c0f\u5199\u5426\u5219\u8303\u56f4for\u5c31\u62a5\u9519<\/p>\n
\u56e0\u4e3astring\u7c7b\u7684\u6210\u5458\u53d8\u91cf\u662f\u79c1\u6709\u7684，\u6211\u4eec\u5e76\u4e0d\u80fd\u76f4\u63a5\u5bf9\u5176\u8fdb\u884c\u8bbf\u95ee，\u6240\u4ee5string\u7c7b\u8bbe\u7f6e\u4e86size\u548ccapacity\u8fd9\u4e24\u4e2a\u6210\u5458\u51fd\u6570，\u7528\u4e8e\u83b7\u53d6string\u5bf9\u8c61\u7684\u5927\u5c0f\u548c\u5bb9\u91cf\u3002 size\u51fd\u6570\u7528\u4e8e\u83b7\u53d6\u5b57\u7b26\u4e32\u5f53\u524d\u7684\u6709\u6548\u957f\u5ea6（\u4e0d\u5305\u62ec\u2019\\\\0\u2019）\u3002<\/p>\n
size_t size() const
\n{
\nreturn _size;
\n} <\/p>\n
capacity\u51fd\u6570\u7528\u4e8e\u83b7\u53d6\u5b57\u7b26\u4e32\u5f53\u524d\u7684\u5bb9\u91cf\u3002（\u4e0d\u5305\u62ec\u2019\\\\0\u2019）\u3002<\/p>\n
size_t capacity() const
\n{
\nreturn _capacity;
\n} <\/p>\n
reserve\u548cresize\u8fd9\u4e24\u4e2a\u51fd\u6570\u7684\u6267\u884c\u89c4\u5219\u4e00\u5b9a\u8981\u533a\u5206\u6e05\u695a\u3002 reserve\u89c4\u5219： \u20031\u3001\u5f53n\u5927\u4e8e\u5bf9\u8c61\u5f53\u524d\u7684capacity\u65f6，\u5c06capacity\u6269\u5927\u5230n\u6216\u5927\u4e8en\u3002 \u20032\u3001\u5f53n\u5c0f\u4e8e\u5bf9\u8c61\u5f53\u524d\u7684capacity\u65f6，\u4ec0\u4e48\u4e5f\u4e0d\u505a\u3002<\/p>\n
void reserve(size_t n)
\n{
\nif (n > _capacity)
\n{
\nchar* tmp = new char[n + 1];\/\/\u591a\u5f00\u4e00\u4e2a\u7a7a\u95f4\u7528\u4e8e\u5b58\u653e'\\\\0'
\nstrcpy(tmp, _str);
\ndelete[] _str;<\/p>\n
_str = tmp;
\n_capacity = n;<\/p>\n
}
\n} <\/p>\n
resize\u89c4\u5219：<\/p>\n
1\u3001\u5f53n\u5927\u4e8e\u5f53\u524d\u7684size\u65f6，\u5c06size\u6269\u5927\u5230n，\u6269\u5927\u7684\u5b57\u7b26\u4e3ach，\u82e5ch\u672a\u7ed9\u51fa，\u5219\u9ed8\u8ba4\u4e3a\u2019\\\\0\u2019\u3002 2\u3001\u5f53n\u5c0f\u4e8e\u5f53\u524d\u7684size\u65f6，\u5c06size\u7f29\u5c0f\u5230n\u3002<\/p>\n
\/\/\u6539\u53d8\u5927\u5c0f
\nvoid resize(size_t n, char ch = '\\\\0')
\n{
\nif (n <= _size)
\n{
\n_size = n;
\n_str[_size] = '\\\\0';
\n}
\nelse
\n{
\nif (n > _capacity)
\n{
\nreserve(n);
\n}
\nfor (size_t i = _size; i < n; i++)
\n{
\n_str[i] = ch;
\n}
\n_size = n;
\n_str[_size] = '\\\\0';
\n}
\n} <\/p>\n
void push_back(char c)
\n{
\nif (_size == _capacity)
\n{
\nreserve(_capacity == 0 ? 4 : 2 * _capacity);
\n}
\n_str[_size] = c; \/\/ \u5728\u7ed3\u5c3e\u4f4d\u7f6e\u5199\u5165\u65b0\u5b57\u7b26（\u8986\u76d6\u539f'\\\\0'）
\n _size++; \/\/ \u589e\u52a0\u957f\u5ea6
\n _str[_size] = '\\\\0'; \/\/ \u5728\u65b0\u7ed3\u5c3e\u8865\u7ec8\u6b62\u7b26
\n} <\/p>\n
\u5b9e\u73b0push_back\u8fd8\u53ef\u4ee5\u76f4\u63a5\u590d\u7528\u4e0b\u9762\u5373\u5c06\u5b9e\u73b0\u7684insert\u51fd\u6570\u3002<\/p>\n
\/\/\u5c3e\u63d2\u5b57\u7b26
\nvoid push_back(char ch)
\n{
\ninsert(_size, ch); \/\/\u5728\u5b57\u7b26\u4e32\u672b\u5c3e\u63d2\u5165\u5b57\u7b26ch
\n}<\/p>\n
\/\/\u5c3e\u63d2\u5b57\u7b26\u4e32
\nvoid append(const char* str)
\n{
\nsize_t len = strlen(str);
\nif (_size + len > _capacity)
\n{
\nsize_t newCapacity = 2 * _capacity;
\n\/\/ \u62692\u500d\u4e0d\u591f，\u5219\u9700\u8981\u591a\u5c11\u6269\u591a\u5c11
\nif (newCapacity < _size + len)
\nnewCapacity = _size + len;
\nreserve(newCapacity);
\n}\/\/\u907f\u514d\u5c3e\u63d2\u5b57\u7b26\u4e32\u65f6\u5982\u679c\u5b57\u7b26\u4e32\u5927\u4e8e\u4e8c\u500d_capacity\u65f6\u7684\u591a\u6b21\u6269\u5bb9<\/p>\n
strcpy(_str + _size, str);
\n_size += len;
\n} <\/p>\n
+=\u8fd0\u7b97\u7b26\u7684\u91cd\u8f7d\u662f\u4e3a\u4e86\u5b9e\u73b0\u5b57\u7b26\u4e32\u4e0e\u5b57\u7b26\u3001\u5b57\u7b26\u4e32\u4e0e\u5b57\u7b26\u4e32\u4e4b\u95f4\u80fd\u591f\u76f4\u63a5\u4f7f\u7528+=\u8fd0\u7b97\u7b26\u8fdb\u884c\u5c3e\u63d2\u3002 +=\u8fd0\u7b97\u7b26\u5b9e\u73b0\u5b57\u7b26\u4e32\u4e0e\u5b57\u7b26\u4e4b\u95f4\u7684\u5c3e\u63d2\u76f4\u63a5\u8c03\u7528push_back\u51fd\u6570\u5373\u53ef\u3002<\/p>\n
\/\/+=\u8fd0\u7b97\u7b26\u91cd\u8f7d
\nstring& operator+=(char ch)
\n{
\npush_back(ch); \/\/\u5c3e\u63d2\u5b57\u7b26\u4e32
\nreturn *this; \/\/\u8fd4\u56de\u5de6\u503c（\u652f\u6301\u8fde\u7eed+=）
\n}<\/p>\n
+=\u8fd0\u7b97\u7b26\u5b9e\u73b0\u5b57\u7b26\u4e32\u4e0e\u5b57\u7b26\u4e32\u4e4b\u95f4\u7684\u5c3e\u63d2\u76f4\u63a5\u8c03\u7528append\u51fd\u6570\u5373\u53ef\u3002<\/p>\n
\/\/+=\u8fd0\u7b97\u7b26\u91cd\u8f7d
\nstring& operator+=(const char* str)
\n{
\nappend(str); \/\/\u5c3e\u63d2\u5b57\u7b26\u4e32
\nreturn *this; \/\/\u8fd4\u56de\u5de6\u503c（\u652f\u6301\u8fde\u7eed+=）
\n}<\/p>\n
insert\u51fd\u6570\u7684\u4f5c\u7528\u662f\u5728\u5b57\u7b26\u4e32\u7684\u4efb\u610f\u4f4d\u7f6e\u63d2\u5165\u5b57\u7b26\u6216\u662f\u5b57\u7b26\u4e32\u3002<\/p>\n
void insert(size_t pos, char ch);<\/p>\n
void intsert(size_t pos,const char* str);<\/p>\n
<\/p>\n
void intsert(size_t pos, char ch)
\n{
\nif (_size == _capacity)
\n{
\nreserve(_capacity == 0 ? 4 : 2 * _capacity);
\n}
\nsize_t end = _size;
\nwhile (end >=(int)pos)
\n{
\n_str[end + 1] = _str[end];
\nend–;
\n}
\n_str[pos] = ch;
\n_size++;
\n} <\/p>\n
insert\u51fd\u6570\u63d2\u5165\u5b57\u7b26\u4e32\u65f6\u4e5f\u662f\u7c7b\u4f3c\u601d\u8def<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/08\/20250816000601-689fcb69110bd.jpg\")
<\/p>\n
void intsert(size_t pos, const char* str)
\n{
\nsize_t len = strlen(str);
\nif (_size + len > _capacity)
\n{
\nsize_t newCapacity = 2 * _capacity;
\n\/\/ \u62692\u500d\u4e0d\u591f，\u5219\u9700\u8981\u591a\u5c11\u6269\u591a\u5c11
\nif (newCapacity < _size + len)
\nnewCapacity = _size + len;
\nreserve(newCapacity);
\n}
\nsize_t end = _size + len;
\nwhile (end > pos + len – 1)
\n{
\n_str[end] = _str[end – len];
\n–end;
\n}<\/p>\n
for (size_t i = 0; i < len; i++)
\n{
\n_str[pos + i] = str[i];
\n}<\/p>\n
_size += len;
\n} <\/p>\n
erase\u51fd\u6570\u7684\u4f5c\u7528\u662f\u5220\u9664\u5b57\u7b26\u4e32\u4efb\u610f\u4f4d\u7f6e\u5f00\u59cb\u7684n\u4e2a\u5b57\u7b26\u3002<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2025\/08\/20250816000601-689fcb69dedb1.jpg\")
<\/p>\n
void erase(size_t pos, size_t len)
\n{
\nassert(pos < _size);
\nif (len >= _size – pos)
\n{
\n_str[pos] = '\\\\0';
\n_size = pos;
\n}
\nelse
\n{ \/\/\u4ece\u540e\u5f80\u524d\u632a
\nsize_t end = pos + len;
\nwhile (end <= _size)
\n{
\n_str[end-len] = _str[end];\/\/\u8986\u76d6pos\u53ca\u540elen\u957f\u5ea6\u7684\u503c，\u5b8c\u6210\u5220\u9664
\nend++;
\n}
\n_size -= len;
\n}
\n}<\/p>\n
clear\u51fd\u6570\u7528\u4e8e\u5c06\u5bf9\u8c61\u4e2d\u5b58\u50a8\u7684\u5b57\u7b26\u4e32\u7f6e\u7a7a，\u5b9e\u73b0\u65f6\u76f4\u63a5\u5c06\u5bf9\u8c61\u7684_size\u7f6e\u7a7a，\u7136\u540e\u5728\u5b57\u7b26\u4e32\u540e\u9762\u653e\u4e0a\u2019\\\\0\u2019\u5373\u53ef<\/p>\n
\/\/\u6e05\u7a7a\u5b57\u7b26\u4e32
\nvoid clear()
\n{
\n_size = 0; \/\/size\u7f6e\u7a7a
\n_str[_size] = '\\\\0'; \/\/\u5b57\u7b26\u4e32\u540e\u9762\u653e\u4e0a'\\\\0'
\n}<\/p>\n
[ ]\u8fd0\u7b97\u7b26\u7684\u91cd\u8f7d\u662f\u4e3a\u4e86\u8ba9string\u5bf9\u8c61\u80fd\u50cfC\u5b57\u7b26\u4e32\u4e00\u6837，\u901a\u8fc7[ ] +\u4e0b\u6807\u7684\u65b9\u5f0f\u83b7\u53d6\u5b57\u7b26\u4e32\u5bf9\u5e94\u4f4d\u7f6e\u7684\u5b57\u7b26\u3002<\/p>\n
\/\/[]\u8fd0\u7b97\u7b26\u91cd\u8f7d（\u53ef\u8bfb\u53ef\u5199）
\nchar& operator[](size_t i)
\n{
\nassert(i < _size); \/\/\u68c0\u6d4b\u4e0b\u6807\u7684\u5408\u6cd5\u6027
\nreturn _str[i]; \/\/\u8fd4\u56de\u5bf9\u5e94\u5b57\u7b26
\n}<\/p>\n
\u5728\u67d0\u4e9b\u573a\u666f\u4e0b，\u6211\u4eec\u53ef\u80fd\u53ea\u80fd\u7528[ ] +\u4e0b\u6807\u7684\u65b9\u5f0f\u8bfb\u53d6\u5b57\u7b26\u800c\u4e0d\u80fd\u5bf9\u5176\u8fdb\u884c\u4fee\u6539\u3002\u4f8b\u5982，\u5bf9\u4e00\u4e2aconst\u7684string\u7c7b\u5bf9\u8c61\u8fdb\u884c[ ] +\u4e0b\u6807\u7684\u64cd\u4f5c，\u6211\u4eec\u53ea\u80fd\u8bfb\u53d6\u6240\u5f97\u5230\u7684\u5b57\u7b26，\u800c\u4e0d\u80fd\u5bf9\u5176\u8fdb\u884c\u4fee\u6539\u3002\u6240\u4ee5\u6211\u4eec\u9700\u8981\u518d\u91cd\u8f7d\u4e00\u4e2a[ ] \u8fd0\u7b97\u7b26，\u7528\u4e8e\u53ea\u8bfb\u64cd\u4f5c\u3002<\/p>\n
\/\/[]\u8fd0\u7b97\u7b26\u91cd\u8f7d（\u53ef\u8bfb\u53ef\u5199）
\nconst char& operator[](size_t i)const
\n{
\nassert(i < _size); \/\/\u68c0\u6d4b\u4e0b\u6807\u7684\u5408\u6cd5\u6027
\nreturn _str[i]; \/\/\u8fd4\u56de\u5bf9\u5e94\u5b57\u7b26
\n}<\/p>\n
c_str\u51fd\u6570\u7528\u4e8e\u83b7\u53d6\u5bf9\u8c61C\u7c7b\u578b\u7684\u5b57\u7b26\u4e32<\/p>\n
\/\/\u8fd4\u56deC\u7c7b\u578b\u7684\u5b57\u7b26\u4e32
\nconst char* c_str()const
\n{
\nreturn _str;
\n}<\/p>\n
\u5728 C++ \u6807\u51c6\u5e93\u4e2d，\u200bnpos\u200b \u662f\u4e00\u4e2a\u7279\u6b8a\u7684\u9759\u6001\u5e38\u91cf\u6210\u5458，\u4e3b\u8981\u7528\u4e8e\u8868\u793a\u201c\u65e0\u6548\u4f4d\u7f6e\u201d\u6216\u201c\u672a\u627e\u5230\u201d\u7684\u72b6\u6001<\/p>\n
\u6ce8：\u53ea\u6709\u6574\u5f62\u624d\u80fd\u5728\u58f0\u660e\u4e2d\u5b9a\u4e49<\/p>\n
static const size_t npos=-1; <\/p>\n
\u00a0\u200b\u6838\u5fc3\u7528\u9014<\/p>\n
(1) \u200b\u67e5\u627e\u51fd\u6570\u5931\u8d25\u65f6\u7684\u8fd4\u56de\u503c<\/p>\n
std::string str = "Hello";
\nsize_t pos = str.find('x'); \/\/ \u67e5\u627e\u4e0d\u5b58\u5728\u5b57\u7b26
\nif (pos == std::string::npos) { \/\/ \u5fc5\u987b\u7528 npos \u68c0\u67e5
\n std::cout << "Not found!";
\n} <\/p>\n
(2) \u200b\u8868\u793a\u201c\u76f4\u5230\u5b57\u7b26\u4e32\u672b\u5c3e\u201d\u200b<\/p>\n
std::string sub = str.substr(2, std::string::npos); \/\/ \u4ece\u7d22\u5f152\u5230\u672b\u5c3e <\/p>\n
\u7279\u6027<\/p>\n
\u200b\u65e0\u7b26\u53f7\u503c\u200b：\u7531\u4e8e\u662f\u00a0size_t\u7c7b\u578b，\u907f\u514d\u76f4\u63a5\u4e0e\u00a0-1\u6bd4\u8f83，\u800c\u5e94\u4f7f\u7528\u00a0npos\u3002\u2022<\/p>\n<\/li>\n
\u200b\u8db3\u591f\u5927\u200b：\u5176\u503c（\u5982 18446744073709551615）\u4fdd\u8bc1\u4e0d\u4f1a\u4e0e\u4efb\u4f55\u6709\u6548\u7d22\u5f15\u51b2\u7a81\u3002<\/p>\n<\/li>\n<\/ul>\n
find\u51fd\u6570\u662f\u7528\u4e8e\u5728\u5b57\u7b26\u4e32\u4e2d\u67e5\u627e\u4e00\u4e2a\u5b57\u7b26\u6216\u662f\u5b57\u7b26\u4e32<\/p>\n
find\u51fd\u6570：\u6b63\u5411\u67e5\u627e\u5373\u4ece\u5b57\u7b26\u4e32\u5f00\u5934\u5f00\u59cb\u5411\u540e\u67e5\u627e<\/p>\n
1\u3001\u6b63\u5411\u67e5\u627e\u7b2c\u4e00\u4e2a\u5339\u914d\u7684\u5b57\u7b26\u3002<\/p>\n
size_t find(char ch,size_t pos=0)
\n{
\n\/\/\u9ed8\u8ba4\u4ece\u9996\u5b57\u7b26\u5f00\u59cb\u67e5\u627e
\nassert(pos<_size);
\nfor (size_t i = pos; i < _size; i++)
\n{
\nif (_str[i] == ch)
\n{
\nreturn i;
\n}<\/p>\n
}
\n\/\/\u627e\u4e0d\u5230\u8fd4\u56denpos
\nreturn npos;
\n} <\/p>\n
2\u3001\u6b63\u5411\u67e5\u627e\u7b2c\u4e00\u4e2a\u5339\u914d\u7684\u5b57\u7b26\u4e32\u3002<\/p>\n
\u8fd9\u91cc\u7528\u5230\u4e86\u4e00\u4e2astrstr\u51fd\u6570<\/p>\n
char * strstr (char * str1, const char * str2 ); <\/p>\n
\u8fd4\u56de\u6307\u5411 str1 \u4e2d\u7b2c\u4e00\u6b21\u51fa\u73b0\u7684 str2 \u7684\u6307\u9488，\u5982\u679c str2 \u4e0d\u662f str1 \u7684\u4e00\u90e8\u5206，\u5219\u8fd4\u56de\u7a7a\u6307\u9488\u3002<\/p>\n
size_t find(const char* str, size_t pos = 0)
\n{
\nassert(pos < _size);
\nconst char* ptr = strstr(_str, str);
\nif (ptr)\/\/\u5982\u679c\u627e\u5230\u4e86
\n{
\nreturn ptr – _str; \/\/\u4e0b\u6807
\n}
\nelse \/\/\u4e3a\u7a7a
\n{
\nreturn npos;
\n}
\n} <\/p>\n
substr\u51fd\u6570\u7528\u6765\u53d6\u5b57\u7b26\u4e32\u4e2d\u7684\u5b50\u5b57\u7b26\u4e32，\u4f4d\u7f6e\u548c\u957f\u5ea6\u7531\u81ea\u5df1\u51b3\u5b9a<\/p>\n
\u9ed8\u8ba4\u4ece\u9996\u5b57\u7b26\u53d6，\u9ed8\u8ba4\u53d6\u7684\u957f\u5ea6\u662f\u53d6\u5230\u5c3e<\/p>\n
string substr (size_t pos = 0, size_t len = npos) const；<\/p>\n
\u8c03\u7528\u62f7\u8d1d\u6784\u9020，\u8fd4\u56depos\u4f4d\u540elen\u957f\u5ea6\u7684\u5b57\u7b26\u4e32<\/p>\n
string substr(size_t pos, size_t len)
\n{
\nassert(pos < _size);
\n\/\/len\u957f\u5ea6\u8db3\u591f\u5927\u5c31\u76f4\u63a5\u53d6\u5230\u5c3e
\nif (len > _size – pos)
\n{
\nlen = _size – pos;
\n}
\nstring sub;
\nsub.reserve(len);
\nfor (size_t i = pos;i < len; i++)
\n{
\nsub += _str[pos + i];
\n}<\/p>\n
return sub;
\n} <\/p>\n
\u5173\u7cfb\u8fd0\u7b97\u7b26\u6709 >\u3001>=\u3001<\u3001<=\u3001==\u3001!= \u8fd9\u516d\u4e2a，\u4f46\u662f\u5bf9\u4e8eC++\u4e2d\u4efb\u610f\u4e00\u4e2a\u7c7b\u7684\u5173\u7cfb\u8fd0\u7b97\u7b26\u91cd\u8f7d，\u6211\u4eec\u5747\u53ea\u9700\u91cd\u8f7d\u5176\u4e2d\u7684\u4e24\u4e2a，\u5269\u4e0b\u7684\u56db\u4e2a\u5173\u7cfb\u8fd0\u7b97\u7b26\u53ef\u4ee5\u901a\u8fc7\u590d\u7528\u5df2\u7ecf\u91cd\u8f7d\u597d\u4e86\u7684\u4e24\u4e2a\u5173\u7cfb\u8fd0\u7b97\u7b26\u6765\u5b9e\u73b0\u3002<\/p>\n
\u4f8b\u5982，\u5bf9\u4e8estring\u7c7b，\u6211\u4eec\u53ef\u4ee5\u9009\u62e9\u53ea\u91cd\u8f7d <\u00a0\u548c == \u8fd9\u4e24\u4e2a\u5173\u7cfb\u8fd0\u7b97\u7b26\u3002<\/p>\n
\u6ce8：\u91cd\u8f7d\u5728\u7c7b\u5916\u9762，\u547d\u540d\u57df\u4f8b：lzg\u91cc\u3002\u8fd9\u6837\u64cd\u4f5c\u6570\u5c31\u4e0d\u7528\u9650\u5b9a\u6b7b\u662fstring\u7c7b\u7684<\/p>\n
\u200blhs\u200b：\u4ee3\u8868 \u200bLeft-Hand \u200bSide (\u5de6\u4fa7\u64cd\u4f5c\u6570\/\u5de6\u4fa7\u503c)<\/p>\n
\u200brhs\u200b：\u4ee3\u8868 \u200bRight-Hand \u200bSide (\u53f3\u4fa7\u64cd\u4f5c\u6570\/\u53f3\u4fa7\u503c)<\/p>\n
\/\/==\u8fd0\u7b97\u7b26\u91cd\u8f7d
\nbool operator== (const string& lhs, const string& rhs)
\n{
\nreturn strcmp(lhs.c_str(), rhs.c_str()) == 0;
\n}<\/p>\n
\/\/<\u8fd0\u7b97\u7b26\u91cd\u8f7d
\nbool operator< (const string& lhs, const string& rhs)
\n{
\nreturn strcmp(lhs.c_str(), rhs.c_str()) < 0;
\n} <\/p>\n
\u5269\u4e0b\u7684\u56db\u4e2a\u5173\u7cfb\u8fd0\u7b97\u7b26\u7684\u91cd\u8f7d，\u5c31\u53ef\u4ee5\u901a\u8fc7\u590d\u7528\u8fd9\u4e24\u4e2a\u5df2\u7ecf\u91cd\u8f7d\u597d\u4e86\u7684\u5173\u7cfb\u8fd0\u7b97\u7b26\u6765\u5b9e\u73b0\u4e86\u3002<\/p>\n
\/\/<=\u8fd0\u7b97\u7b26\u91cd\u8f7d
\nbool operator<= (const string& lhs, const string& rhs)
\n{
\nreturn lhs < rhs || lhs == rhs;
\n}<\/p>\n
\/\/!=\u8fd0\u7b97\u7b26\u91cd\u8f7d
\nbool operator!= (const string& lhs, const string& rhs)
\n{
\nreturn !(lhs == rhs);
\n}<\/p>\n
\/\/>\u8fd0\u7b97\u7b26\u91cd\u8f7d
\nbool operator> (const string& lhs, const string& rhs)
\n{
\nreturn !(lhs <= rhs);
\n}<\/p>\n
\/\/>=\u8fd0\u7b97\u7b26\u91cd\u8f7d
\nbool operator>= (const string& lhs, const string& rhs)
\n{
\nreturn !(lhs < rhs);
\n} <\/p>\n
>>\u8fd0\u7b97\u7b26\u7684\u91cd\u8f7d<\/p>\n
ostream& operator<<(ostream& os, const string& str)
\n{
\nfor (size_t i = 0; i < str.size(); i++)
\n{<\/p>\n
os << str[i];
\n}<\/p>\n
return os;
\n} <\/p>\n
<<\u8fd0\u7b97\u7b26\u7684\u91cd\u8f7d<\/p>\n
istream& operator>>(istream& is, string& str)
\n{
\nstr.clear();<\/p>\n
char ch;
\n\/\/is >> ch;
\nch = is.get();
\nwhile (ch != ' ' && ch != '\\\\n')
\n{
\nstr += ch;
\nch = is.get();
\n}<\/p>\n
return is;
\n} <\/p>\n","protected":false},"excerpt":{"rendered":"
\u6587\u7ae0\u6d4f\u89c8\u9605\u8bfb110\u6b21\uff0c\u70b9\u8d5e3\u6b21\uff0c\u6536\u85cf4\u6b21\u3002\u672c\u6587\u5b9e\u73b0\u4e86\u4e00\u4e2a\u7b80\u6613\u7684string\u7c7b\uff0c\u4e3b\u8981\u5305\u542b\u4ee5\u4e0b\u529f\u80fd\uff1a1. \u9ed8\u8ba4\u6210\u5458\u51fd\u6570\uff1a\u6784\u9020\u51fd\u6570\uff08\u9ed8\u8ba4\/\u53c2\u6570\u5316\uff09\u3001\u62f7\u8d1d\u6784\u9020\u3001\u8d4b\u503c\u91cd\u8f7d\u548c\u6790\u6784\u51fd\u6570\uff0c\u91c7\u7528\u6df1\u62f7\u8d1d\u907f\u514d\u5185\u5b58\u95ee\u9898\uff1b2. \u8fed\u4ee3\u5668\u652f\u6301\uff1a\u901a\u8fc7char*\u5b9e\u73b0begin()\/end()\u8fed\u4ee3\u5668\uff1b3. \u5bb9\u91cf\u64cd\u4f5c\uff1asize()\/capacity()\u83b7\u53d6\u5927\u5c0f\u5bb9\u91cf\uff0creserve()\/resize()\u8c03\u6574\u7a7a\u95f4\uff1b4. \u5b57\u7b26\u4e32\u4fee\u6539\uff1apush_back()\u3001append()\u3001insert()\u3001erase()\u7b49\u64cd\u4f5c\uff1b5. \u8bbf\u95ee\u64cd\u4f5c\uff1a\u91cd\u8f7doperator[]\u548cc_str()\u65b9\u6cd5\uff1b6. \u5b9e\u7528\u529f\u80fd\uff1a<\/p>\n","protected":false},"author":2,"featured_media":58306,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[55,87,427],"topic":[],"class_list":["post-58309","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-server","tag-c","tag-87","tag-427"],"yoast_head":"\n