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Function Reference

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#define E_VALUE_ERROR

0x08000000

#define E_FONT_ERROR

0x10000000

#define E_FATAL_ERROR

0x20000000

#define E_FILE_ERROR

0x40000000

At time of publication only one flag is set at any one time. Future versions may be set multiple flags,

e.g. E_SYNTAX_ERROR and E_WARNING. Because of this, it is recommended to mask out the

error type with a bitwise and operator.

If the callback function returns a value other than zero (0), processing stops immediately.

Return values:

If the function succeeds the return value is 1. If the function fails the return value is 0.

SetOnPageBreakProc

Syntax:

LBOOL pdfSetOnPageBreakProc(

const PPDF* IPDF,

// Instance pointer

const void* Data,

// User defined pointer or NULL

const void* OnBreakProc) // Callback function, see below

#define PDF_CALL __stdcall

// Windows only, otherwise empty

typedef SI32 PDF_CALL TOnPageBreakProc(

const void* Data,

// User defined pointer

double LastPosX,

// Last x-coordinate of the string

double LastPosY,

// Last y-coordinate of the string

LBOOL PageBreak);

// True, if a manual page break occurred

The function sets a callback function which is called by WriteFText() when a page break occurred.

The parameter Data holds a user defined pointer which is passed unchanged to the callback

function. If this pointer is not required set it to NULL. The calling convention of the callback

function is standard call on Windows.

The Visual Basic and VB .Net interfaces use events instead of a callback function, see Language

Binding Visual Basic or VB .Net for further information). In VB .Net you can use a callback function

or the event. The OnPageBreakProc event must be connected manually in these interfaces to avoid

different runtime behaviour of the function WriteFText(). To enable the event call the function

ConnectPageBreakEvent() in VB or VB .Net.

The parameter PageBreak of the callback function specifies why the callback function was called:

• If true, a page break tag in the string was found (see WriteFText() for further information).

• If false, the output rectangle was filled with text entirely.

The usage of the callback function is described in detail under WriteFText(). However, the following

return values of the callback function can be used the change the text alignment:

#define NEW_ALIGN_LEFT

#define NEW_ALIGN_RIGHT

#define NEW_ALIGN_CENTER

#define NEW_ALIGN_JUSTIFY 4

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