实现几个字符串常用函数

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实现几个字符串常用函数，练习一下写代码。经常谢谢代码，使自己不要忘了如何写代码。

字符比较函数

字符串赋值函数

求字符串长度

字符串那倒置

字符串比较

字符串连接

// string.cpp : Defines the entry point for the console application.//#include "stdafx.h"#include <assert.h>#include "string.h"//字符交换函数void charswap(char& ch1, char& ch2){char ch = ch1;ch1 = ch2;ch2 = ch;}//求字符串长度int stringlength(const char* sourstr){const char *pstr = sourstr;int length = 0;while(*pstr++ != '\0'){length++;}return length;}//字符串那倒置char* stringconvert(char* sourstr){int length = stringlength(sourstr);int loopnumber = length / 2;int index = 0;while(index < loopnumber){charswap(*(sourstr + index), *(sourstr + length - index - 1));index++;}return sourstr;}//字符串复制char* stringcopy(char* deststr, const char* sourstr){const char* pstr = sourstr;int index = 0;while(*pstr != '\0'){*(deststr + index) = *pstr++;index++;}*(deststr + index) = '\0';return deststr;}//字符串连接char* stringcontact(char* deststr, const char* sourstr){const char* pstr = sourstr;int length = stringlength(deststr);int index = 0;while(*pstr != '\0'){*(deststr + length + index) = *pstr++;index++;}*(deststr + length + index ) = '\0';return deststr;}//字符串比较函数int stringcompare(const char* deststr, const char* sourstr){const char* pdest = deststr;const char* psour = sourstr;while(*pdest == *psour && *pdest != '\0'){pdest++;psour++;}return *pdest - *psour;}int main(int argc, char* argv[]){ char buff1[100];char buff2[100];stringcopy(buff1, "reqre12345");stringcopy(buff2, "reqre1");printf("%d\n", stringcompare(buff1, buff2));getchar();return 0;}