GetFileSize ()

From ISXKB

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Revision as of 09:37, 3 September 2009

This article shows how to use the Windows API function GetFileSize with Inno Setup. This example ignores the high part of the file size.

Contents 1 Declaration 2 GetFileSize () at MSDN 3 Examples 4 See Also

Declaration

The following declaration is required in a [Code] section:

function GetFileSize (hFile: THandle; var lpFileSizeHigh: Integer): Integer;
 external 'GetFileSize@kernel32.dll stdcall';

This declaration works with files up to 2 GB.

GetFileSize () at MSDN

• GetFileSize ()

Examples

This is an example on how to implement a function GetTheFileSize () which opens a file, retrieves its low 32 bit part of the file size as an integer, and closes the file again.

[Code]
function GetFileSize (hFile: THandle; var lpFileSizeHigh: Integer): Integer;
 external 'GetFileSize@kernel32.dll stdcall';

function GetTheFileSize (FileName: String): Integer;
var
	hFile:	THandle;
	iSize:	Integer;
	hSize:	Integer;
begin
	hFile := CreateFile (FileName,
		GENERIC_READ,// Desired access.
		FILE_SHARE_READ + FILE_SHARE_WRITE,
		0,                // Security attributes.
		OPEN_EXISTING,
		FILE_ATTRIBUTE_TEMPORARY,
		0);
	if (INVALID_HANDLE_VALUE = hFile) then
	begin
		Result := 0;
		Exit;
	end;
	iSize := GetFileSize (hFile, hSize);
	CloseHandle (hFile);
	Result := iSize;
end;

See Also

• CreateFile ()
• ClosHandle ()
• ReadFile ()
• WriteFile ()