字符串拷贝的问题

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前段时间想写个拷贝字符串的程序,后来觉得太危险了:

for (int i = 0; i < MAX_PATH; i++)
   {
    StrLog[i] = wcsBuf[i];
   }
      

网友的:

 

编程实现函数void strcopy(char *dest,char *src),要求该函数实现将src中的内容拷贝到dest中。(不许直接调用其他函数来实现)
#include <iostream.h>
#include<string.h>
#include <stdlib.h>

void strcopy(char *dest,char *src);

void main()
{
 char src[20],dest[20];
 cout<<"please input a character string,the length <="<<sizeof(src)<<":";
 cin>>src;
 if(strlen(src)>sizeof(src))
 {
  cerr<<"error!the length of character string is too bigger!/n";
  exit(1);
 }
 else
 {
  cout<<"the old character string is:"<<src<<endl;
  cout<<"the new character string is:";
  strcopy(dest,src);
 }
}

void strcopy(char * dest,char *src)
{
 int n=strlen(src);
 dest=new char[n];
 dest[n]='/0';
 for(int i=0;i<=n-1;i++)
 {
  dest[i]=*src++;
 }
 cout<<dest<<endl;
}

     
                               
   程序所输入的数据类型定义为字符型
   程序运行结果示例:
    please input a character string,the length <=20:www.fly263.com
    the old character string is:www.fly263.com
    the new character string is:www.fly263.com

==============================================================

char *my_strcpy_1(char *str1 ,char *str2)
{
     while((*str1++ = *str2++) != '/0')
                   ;
     return str1;
}

===================================================================================

如果发现有更好的写法,Carpicorn会更新的。:-)

/*
**  Copy the string contained in the second argument to the
** buffer specified by the first argument. 用第一个字符串的空间之间保存拷贝过来的字符串
*/
#include <assert.h>
void strcpy( char *buffer, char const *string )
{
 /*
 ** Copy characters until a NUL byte is copied.
 */
 assert(buffer!=null && string !=null);
 
 while( (*buffer++ = *string++) != '/0' )
                      ;

方法二:

/*
** Make a copy of a string in dynamically allocated memory.  Note:
** caller is responsible for checking whether the memory was
** allocated!  This allows the caller to respond to an error in
** any way they wish.
*/
#include <stdlib.h>
#include <string.h>

char * strdup( char const *string )
{
 char *new_string;

 /*
 ** Ask for enough memory to hold the string and its
 ** terminating NUL byte.
 */
 new_string = malloc( strlen( string ) + 1 );

 /*
 ** If we got the memory, copy the string.
 */
 if( new_string != NULL )
  strcpy( new_string, string );

 return new_string;
}

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