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copied!<p>You have several flaws in your code</p> <ol> <li><p>When you uses the <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/aa363858%28v=vs.85%29.aspx" rel="noreferrer">CreateFile</a> function you must check the returned handle against the INVALID_HANDLE_VALUE.</p></li> <li><p>Always you must use try .. finally to free the resources.</p></li> <li><p>You are trying to use the <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/aa365467%28v=vs.85%29.aspx" rel="noreferrer">ReadFile</a> function reading the contents inside of the <code>thefile</code> buffer using a index 1, this is wrong you must use a index 0 because the dynamic arrays are zero index based.</p></li> <li><p>you are using this code </p></li> </ol> <blockquote> <p>CloseHandle(CreateFileA (sfile, 0, 0,NIL, CREATE_NEW, FILE_ATTRIBUTE_NORMAL,0));</p> </blockquote> <p>To create an empty file and then using again the CreateFile function to open and write the file, you can do the same in one step </p> <pre><code> FileHandle := CreateFileA(sFile, GENERIC_WRITE, FILE_SHARE_WRITE, nil, CREATE_NEW, 0, 0); </code></pre> <p>Try this improved version of your code.</p> <p>Btw, there is nothing wrong with use SetLengh, the problem is explained in the point 3.</p> <pre><code>var thefile : array of AnsiChar; begin FileHandle := CreateFileA(paramstr0, GENERIC_READ, FILE_SHARE_READ, nil, OPEN_EXISTING, 0, 0); if FileHandle <> INVALID_HANDLE_VALUE then try dwSize := GetFileSize(FileHandle, nil); SetFilePointer(FileHandle, 0, nil, FILE_BEGIN); SetLength(TheFile, dwsize); ReadFile(FileHandle, thefile[0], dwSize , dwRead, nil); finally CloseHandle (FileHandle); end; FileHandle := CreateFileA(sFile, GENERIC_WRITE, FILE_SHARE_WRITE, nil, CREATE_NEW, 0, 0); if FileHandle <> INVALID_HANDLE_VALUE then try WriteFile (FileHandle, thefile[0], dwSize, testCardinal, nil); finally CloseHandle (FileHandle); end; SetLength(TheFile, 0); end; </code></pre>

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