老大,簡單的文件操作程序,不知道錯在那裡!救命阿
新建一個專案,在窗口Form1上加兩個按鈕,一個OpenDialog1,一個SaveDialog1;//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop
#include "Unit1.h"
#include <fstream.h>
#include <dir.h>
#include <sys\stat.h>
#include <malloc.h>
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
unsigned char *BIN_Byte;
long BIN_Byte_Len;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
: TForm(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
char sPath;
struct stat statbuf;
FILE *stream;
getcwd(sPath,sizeof(sPath));
OpenDialog1->InitialDir=sPath;
OpenDialog1->Filter = "BIN_File(*.BIN)|*.BIN|All_File(*.*)|*.*";
OpenDialog1->FileName="fileFrom.BIN";
if(OpenDialog1->Execute())
{
strcpy(sPath,OpenDialog1->FileName.c_str());
stream=fopen(sPath,"rb");
fstat(fileno(stream),&statbuf);
BIN_Byte_Len=statbuf.st_size;
BIN_Byte=(unsigned char *)alloca(BIN_Byte_Len);
for(int i=0;i<BIN_Byte_Len;i++)
fscanf(stream,"%c",&BIN_Byte); //read file
fclose(stream);
}
free(sPath);
free(stream);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button2Click(TObject *Sender)
{
char sPath;
FILE *stream;
getcwd(sPath,sizeof(sPath));//App.Path
strcat(sPath,"\\");
SaveDialog1->InitialDir = sPath;
SaveDialog1->Filter = "BIN_File(*.BIN)|*.BIN|All_File(*.*)|*.*";
SaveDialog1->FileName="fileTo.BIN";
if(SaveDialog1->Execute())
{
strcpy(sPath , SaveDialog1->FileName.c_str());
stream=fopen(sPath,"wb");
for(int i=0;i<BIN_Byte_Len;i++)
fprintf(stream,"%c",&BIN_Byte); //save file
fclose(stream);
}
free(sPath);
free(stream);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormDestroy(TObject *Sender)
{
free(BIN_Byte);
}
//---------------------------------------------------------------------------
打開一個檔案,再另存為另一個新檔案
結果兩個檔案內容一樣
順序不一樣了
檔案前面一段內容跑到結尾去了
就像下面的情況
原來檔案內容:ABCDEFG
新檔案內容:CDEFGAB
老大救救小弟哦
<P>怎麼一個人也沒有阿</P> <P>這個是對2進制文件的操作</P><P>我用的是一個字符一個字符的操作方法</P> <P>問題解決了</P><P>不用回了</P> <P>不知道你找出的问题在那儿，我判断是alloca和malloc的误用。c++中对指针（内存）的操作总是容易出错，这些系统函数的使用，最好先仔细看看help。</P>
<P>alloca:</P>
<P>Allocates temporary stack space.</P>
<P>alloca allocates size bytes on the stack; the allocated space is automatically freed up when the calling function exits.</P>
<P>malloc:</P>
<P>malloc allocates a block of size bytes from the memory heap. It allows a program to allocate memory explicitly as it抯 needed, and in the exact amounts needed.</P>
<P>Allocates main memory.The heap is used for dynamic allocation of variable-sized blocks of memory. Many data structures, for example, trees and lists, naturally employ heap memory allocation.</P>
<P>以下是改后的代码</P>
<P>//---------------------------------------------------------------------------</P>
<P>#include <vcl.h>
#pragma hdrstop</P>
<P>#include "Unit1.h"
#include <fstream.h>
#include <dir.h>
#include <sys\stat.h>
#include <malloc.h>
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
unsigned char *BIN_Byte;
long BIN_Byte_Len;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
: TForm(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
char sPath;
struct stat statbuf;
FILE *stream;</P>
<P> getcwd(sPath,sizeof(sPath));
OpenDialog1->InitialDir=sPath;
OpenDialog1->Filter = "BIN_File(*.BIN)|*.BIN|All_File(*.*)|*.*";
OpenDialog1->FileName="fileFrom.BIN";
if(OpenDialog1->Execute())
{
strcpy(sPath,OpenDialog1->FileName.c_str());
stream=fopen(sPath,"rb");
fstat(fileno(stream),&statbuf);
BIN_Byte_Len=statbuf.st_size;
BIN_Byte=(unsigned char *)malloc(BIN_Byte_Len);
for(int i=0;i<BIN_Byte_Len;i++)
fscanf(stream,"%c",&BIN_Byte); //read file
fclose(stream);
}
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button2Click(TObject *Sender)
{
char sPath;
FILE *stream;
getcwd(sPath,sizeof(sPath));//App.Path
strcat(sPath,"\\");
SaveDialog1->InitialDir = sPath;
SaveDialog1->Filter = "BIN_File(*.BIN)|*.BIN|All_File(*.*)|*.*";
SaveDialog1->FileName="fileTo.BIN";
if(SaveDialog1->Execute())
{
strcpy(sPath , SaveDialog1->FileName.c_str());
stream=fopen(sPath,"wb");
for(int i=0;i<BIN_Byte_Len;i++)
fprintf(stream,"%c",BIN_Byte); //save file
fclose(stream);
}
free(BIN_Byte);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormDestroy(TObject *Sender)
{
if (BIN_Byte!=NULL)
free(BIN_Byte);
}
//---------------------------------------------------------------------------
</P>
<P>free(sPath); free(stream);此两句也有问题。</P>
<P>char sPath;不需要释放；</P>
<P>fclose(stream)已经起到free(stream)的作用</P>
[此贴子已经被作者于2004-6-15 15:16:40编辑过] <P>我已經改成塊處理的方法了</P><P>謝謝你</P>
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