fwrite() 文件损坏 C++
我是 C++ 的新手（从 C# 迁移过来），所以我不太确定这里发生了什么。我想做的是从文件中读取图像并将其写入输出文件，但每当我这样做时，文件的某些部分似乎已损坏。
我已经检查了内存中的数据，它实际上是匹配的，所以我相信罪魁祸首一定是 fwrite() 发生的事情，尽管它总是可能只是我做错了。
这是一些示例数据： http://pastebin.com/x0eZin6K
我的代码：
// used to figure out if reading in one giant swoop has to do with corruption
int BlockSize = 0x200;
// Read the file data
unsigned char* data = new unsigned char[BlockSize];
// Create a new file
FILE* output = fopen(CStringA(outputFileName), "w+");
for (int i = 0; i < *fileSize; i += BlockSize)
{
if (*fileSize - i > BlockSize)
{
ZeroMemory(data, BlockSize);
fread(data, sizeof(unsigned char), BlockSize, file);
// Write out the data
fwrite(data, sizeof(unsigned char), BlockSize, output);
}
else
{
int tempSize = *fileSize - i;
ZeroMemory(data, tempSize);
fread(data, sizeof(unsigned char), tempSize, file);
// Write out the data
fwrite(data, sizeof(unsigned char), tempSize, output);
}
}
// Close the files, we're done with them
fclose(file);
fclose(output);
delete[] data;
delete fileSize;
I'm somewhat of a newbie to C++ (moving from C#) so I'm not exactly sure what's going on here. What I'm trying to do is read an image out of a file and write it to an output file, but whenever I do parts of the file appear to be corrupt.
I've checked the data in memory and it actually matches, so I believe the culprit has to be something going on with fwrite(), although it could always just be something I'm doing wrong.
Here's some sample data: http://pastebin.com/x0eZin6K
And my code:
// used to figure out if reading in one giant swoop has to do with corruption
int BlockSize = 0x200;
// Read the file data
unsigned char* data = new unsigned char[BlockSize];
// Create a new file
FILE* output = fopen(CStringA(outputFileName), "w+");
for (int i = 0; i < *fileSize; i += BlockSize)
{
if (*fileSize - i > BlockSize)
{
ZeroMemory(data, BlockSize);
fread(data, sizeof(unsigned char), BlockSize, file);
// Write out the data
fwrite(data, sizeof(unsigned char), BlockSize, output);
}
else
{
int tempSize = *fileSize - i;
ZeroMemory(data, tempSize);
fread(data, sizeof(unsigned char), tempSize, file);
// Write out the data
fwrite(data, sizeof(unsigned char), tempSize, output);
}
}
// Close the files, we're done with them
fclose(file);
fclose(output);
delete[] data;
delete fileSize;
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评论（2）
您在 Windows 上运行此代码吗？对于不需要文本翻译的文件，您必须以二进制模式打开它们：
这就是输出文件中发生的情况：
C 运行时库有助于将您的
\n翻译为\r\ n。Are you running this code on Windows? For files that don't need text translation, you must open them in binary mode:
This is what happens in your output file:
The C runtime library helpfully translated your
\nto\r\n.您需要通过在模式中添加“b”来将文件作为二进制文件打开。
http://www.cplusplus.com/reference/clibrary/cstdio/fopen/
You need to open the file as a binary by adding "b" to the mode.
http://www.cplusplus.com/reference/clibrary/cstdio/fopen/