Question

此函数正在将文本文件读入char缓冲区并将指针返回到此缓冲区。

char * textfile_to_char(wchar_t *filename)
{
    WIN32_FIND_DATA data;
    if (FindFirstFile(filename,&data)==INVALID_HANDLE_VALUE)
    {
        wchar_t message[256];
        wsprintf(message,L"File could not be found %lp",filename);
        MessageBox(0,message,0,0);
        return NULL;
    }
    else
    {
        HANDLE hFile=CreateFile(filename,GENERIC_READ,FILE_SHARE_READ|FILE_SHARE_WRITE,0,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL|FILE_ATTRIBUTE_READONLY,0);
        if (hFile==INVALID_HANDLE_VALUE)
        {
            wchar_t message[256];
            wsprintf(message,L"Error opening file: %lp",filename);
            MessageBox(0,message,0,0);
            return NULL;
        }   
        else
        {
            OVERLAPPED overlapped;
            memset(&overlapped,0,sizeof(overlapped));
            char * buffer=new char[data.nFileSizeLow];
            ReadFileEx(hFile,buffer,data.nFileSizeLow,&overlapped,0);
            CloseHandle(hFile);
            buffer[data.nFileSizeLow]=0;
            return buffer;
        }
    }
}

现在，这是另一段代码，我使用此函数从此文本中获取openGl着色器

wchar_t filename[512];
wsprintf(filename,L"%s.vtx",_shader_name);
id_vertex_shader=glCreateShader(GL_VERTEX_SHADER);
id_fragment_shader=glCreateShader(GL_FRAGMENT_SHADER);
char *shader_source=textfile_to_char(filename);
char *buffers[2]={shader_source,0};
glShaderSource(id_vertex_shader,1,buffers,0);
delete[] shader_source;
glCompileShader(id_vertex_shader);

和删除[] shader_source实际上让我很困惑，因为a）它不起作用，b）删除shader_source也不起作用。那我怎么删除它？谢谢

Answer 1

您执行异步读取，然后希望立即读取，然后删除文件句柄

添加对GetFileEx和CloseHandle的GetOverlappedResult调用：

ReadFileEx(hFile,buffer,data.nFileSizeLow,&overlapped,0);
WORD bytesRead;
if(!GetOverlappedResult(hFile, &overlapped, &bytesRead, TRUE);){
    //check error and such

}
CloseHandle(hFile);
buffer[bytesRead]=0;

或者只使用没有OVERLAPPED结构的ReadFile：

WORD bytesRead;
ReadFile(hFile,buffer,data.nFileSizeLow,&bytesRead,0);
CloseHandle(hFile);

如何正确删除char * func（）中使用new []分配的char数组？

1 个答案: