# Function Reference

# DllOpen

Opens a DLL file for use in DllCall.

DllOpen ( "filename" )

## Parameters

filename | Filename of the DLL file to open.

## Return Value

Success: | a dll "handle" to be used with subsequent Dll functions.
Failure: | -1 if error occurs.

## Remarks

When finished working with a dll, call the DllClose() function to close it. AutoIt normally closes all files upon termination, but explicitly calling DllClose() is still a good idea.

## Related

DllCall, DllClose

## Example

    Local $hDLL = DllOpen("user32.dll")
    DllCall($hDLL, "int", "MessageBox", "hwnd", 0, "str", "Some text", "str", "Some title", "int", 0)
    DllClose($hDLL)