WPViewPDF exposes all its methods through a set of methods which all mainly execute a command inside the library.

The list of all commands is installed by the setup in pascal language in file WPDF_ViewCommands.PAS.

The command at least needs an ID as parameter, and, depending on the feature other parameters as integer, cardinal, character pointer or record pointer.

VB6

When using VisualBasic 6 with the WPViewPDF OCX please use the method CommandStrEx. Pass an empty string parameter if no string parameter is expected by a certain command.

VCL

When You are using the CXL in Delphi or C++Builder the following methods can be used to execute commands.

In any case a command is send to the viewer window. The different methods are used to add different parameters.

function command(command: Integer): Integer; overload;

function command(command, Param: Integer): Integer; overload;

This methods can also be used. They are provided to offer compatibility with older compilers.

function CommandEx(command: Integer; Param: Cardinal): Integer;

function CommandStr(command: Integer; str: AnsiString): Integer; overload;

function CommandStrEx(command: Integer; str: AnsiString; Param: Cardinal)

: Integer; overload;

function CommandStr(command: Integer; str: WideString): Integer; overload;

function CommandStrEx(command: Integer; str: WideString; Param: Cardinal)

: Integer; overload;

This commands are used when a string result is expected:

function CommandGetStr(command: Integer; Str:String; Param: Cardinal): WideString;

function CommandGetStrA(command: Integer; Str:String; Param: Cardinal): AnsiString;

The commands are defined in the unit WPDF_ViewCommands. They all start with "COMPDF_..."

.NET

The .NET assembly implements this variants of the command function:

public int Command(int commandnr, string StrParam, uint Param)

public int Command(int commandnr, string StrParam, int Param)

public int Command(int commandnr, string StrParam, byte[] BufferParam)

public int Command(int commandnr, string StrParam, int Param)

Also implemented are this two methods to make it easier to convert code provided for the VCL edition to .NET:

public int CommandStrEx(int commandnr, string StrParam="", int Param=0)

public int CommandStr(int commandnr, string StrParam = "")

If a command shoud return a string or a buffer use this functions:

public string CommandGetStr(int CommandID, string StrPar = "", int IntPar = 0)

public byte[] CommandGetStrA(int CommandID, string StrPar = "", int IntPar = 0)

The commands are defined in the namespace WPViewPDF inside the class "commands". So you need to write

Command(commands.COMPDF_.....)

Native C / C++

Here you can use an implementation like this to call the "EX" command which not only passes a string but also an integer parameter.

struct TWPComRecStruct

{

int StrParam;

int WStrParam;

int StrLen;

unsigned int Param;

int IParam1; // not used

int IParam2;

int IParam3;

int IParam4;

int Reserved; // Must be 0

};

int PDFWindow::CommandEx(int cmd, CString StrParam, int Param)

{

int i = StrParam.GetLength()+1;

char *pmb = (char *)malloc( i );

wchar_t *pwc = (wchar_t *)malloc( sizeof( wchar_t ) * i);

strcpy(pmb, StrParam);

mbstowcs( pwc, pmb, i );

TWPComRecStruct rec;

memset(&rec, 0, sizeof(TWPComRecStruct));

rec.Param = Param;

rec.WStrParam = (int)pwc;

rec.StrLen = StrParam.GetLength();

int iRes = SendMessage(WM_PDF_COMMANDEX, cmd, (LPARAM)&rec);

free(pmb);

free(pwc);

return iRes;

}

IDs of the following command groups can be used: