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FRX Device Helper Foundation Class

This class provides methods to read and write printer device information in the Visual FoxPro environment.

Category

System Utilities

Default Catalog

Visual FoxPro Catalog\Foundation Classes\Output\Output Helper Classes

Class

frxDeviceHelper

Base Class

Custom

Class Library

_frxcursor.vcx

Parent Class

Custom

Remarks

This class exposes the algorithms used by ReportOutput.APP, ReportBuilder.APP, and ReportPreview.APP to interpret various printing values and Report (frx) and Label (lbx) table values.

It is primarily useful for developers extending Visual FoxPro reporting functionality. For more information, see Extending Report Functionality in Visual FoxPro.

Properties, Events, Methods

Description

ActualX property

Physical width of page in device units.

Default: 0

ActualY property

Physical length of page in device units.

Default: 0

DpiX property

Logical pixels-per-inch in the X dimension.

Default: 0

DpiY property

Logical pixels-per-inch in the Y dimension.

Default: 0

LoadDeviceInfo method

Parses out print device parameters into member properties given specific device information.

Syntax: LoadDeviceInfo([cDriver, cDevice, cDEVMODE])

Return: logical value representing success

Arguments:

cDriver specifies the printer driver , as stored in a Report table (frx) EXPR field.

cDevice specifies the printer name, as stored in a Report table (frx) EXPR field.

cDEVMODE is a string representing a structure that holds additional printer information, as stored in a Report table TAG2 field.

Remarks: If you omit the optional arguments, this method loads information for the current VFP default printer.

LoadFromFrx method

Loads printer device parameters from an FRX cursor header record. Restores current record number and selected workarea afterwards.

Syntax: LoadDeviceInfo([cFrxAlias])

Return: logical value representing success

Arguments:

cFRXAlias holds the alias of a Report table (frx) currently in use in the environment. This method assumes an alias of "FRX" if you omit the optional cFRXAlias argument.

mmX property

Horizontal page size in millimeters.

Default: 0

mmY property

Vertical page size in millimeters.

Default: 0

OffsetX property

Physical printable page left margin.

Default: 0

OffsetY property

Physical printable page top margin.

Default: 0

Orientation property

Page orientation (0=Portrait, 1=Landscape).

Default: 0

PrintableX property

Horizontal page width in pixels.

Default: 0

PrintableY property

Vertical page length in pixels.

Default: 0

ErrorMessage property

Contains error text if the LoadDeviceInfo() method returns false.

Default: ""

Example

In this example, an instance of the frxDeviceHelper class displays information about resolution in dots (pixels) per inch for the current VFP default printer.

oDeviceHelper = NEWOBJECT( "frxDeviceHelper" ) 
IF oDeviceHelper.LoadDeviceInfo()
    ? oDeviceHelper.DpiX
    ? oDeviceHelper.DpiY
ELSE
    ? oDeviceHelper.ErrorMessage
ENDIF

See Also

Concepts

Guidelines for Using Visual FoxPro Foundation Classes

Reference

Visual FoxPro Foundation Classes A-Z