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The ASCIIPrintClass provides the user interface--a simple Print Options dialog--to print one or more lines from a text file. The ASCIIPrintClass interface lets the end user specify a range of lines to print, then optionally previews the lines before printing them. The ASCIIPrintClass interface also provides access to the standard Windows Print Setup dialog.

**ASCIIPrintClass Relationship to Other Application Builder Classes**

The ASCIIPrintClass relies on the ASCIIFileClass to read and index the file that it prints. It also relies on the PrintPreviewClass to provide the on-line preview. It also uses the TranslatorClass to translate its Print Options dialog text if needed.

The ASCIIViewerClass uses the ASCIIPrintClass to provide the end user with a Print Options dialog to print one or more lines from the viewed file.

There are several related classes whose collective purpose is to provide reusable, read-only, viewing, scrolling, searching, and printing capability for files, including variable length files. Although these classes are primarily designed for ASCII text and they anticipate using the Clarion ASCII Driver to access the files, they also work with binary files and with other database drivers. These classes can be used to build other components and functionality as well.

The classes that provide this read-only functionality are:

|  | ASCIIViewerClass | ASCIIFileClass plus user interface |
|  | ASCIIFileClass | Open, read, filter, and index the file |
|  | ASCIIPrintClass | Print one or more lines |
|  | ASCIISearchClass | Locate and scroll to text |

**ASCIIPrintClass ABC Template Implementation**

Both the Viewer procedure template and the ASCIIPrintButton control template generate code to instantiate an ASCIIPrintClass object. The Viewer template accomplishes this by adding a parameter to the ASCIIViewerClass.Init method. The ASCIIPrintButton template accomplishes this by declaring an ASCIIPrintClass object and calling the ASCIIViewerClass.AddItem method to register the ASCIIPrintClass object with the ASCIIViewerClass object.

**ASCIIPrintClass Source Files**

The ASCIIPrintClass source code is installed by default to the Clarion \LIBSRC folder. The specific ASCIIPrintClass source code and their respective components are contained in:

|  | ABASCII.INC | ASCIIPrintClass declarations |
|  | ABASCII.CLW | ASCIIPrintClass method definitions |

**ASCIIPrintClass Conceptual Example**

The following example shows a typical sequence of statements to declare, instantiate, initialize, use, and terminate an ASCIIPrintClass object and related objects.

This example lets the end user select a file, then search and print from it.

** MEMBER('viewer.clw')**

** INCLUDE('ABASCII.INC')**

** INCLUDE('ABWINDOW.INC')**

** MAP**

**  MODULE('VIEWE002.CLW')**

**BrowseFiles  PROCEDURE**

**  END**

** END**

**BrowseFiles  PROCEDURE**

**FilesOpened   BYTE**

**ViewerActive  BYTE(False)**

**Filename      STRING(FILE:MaxFilePath),AUTO,STATIC,THREAD**

**AsciiFile     FILE,DRIVER('ASCII'),NAME(Filename),PRE(A1),THREAD**

**RECORD         RECORD,PRE()**

**Line            STRING(255)**

**               END**

**              END**

**ViewWindow  WINDOW('View an ASCII File'),AT(3,7,296,136),SYSTEM,GRAY**

**             LIST,AT(5,5,285,110),USE(?AsciiBox),IMM,FROM('')**

**             BUTTON('&Print...'),AT(7,119),USE(?Print)**

**             BUTTON('&Search...'),AT(44,119),USE(?Search)**

**            END**

**ThisWindow  CLASS(WindowManager)**

**Init          PROCEDURE(),BYTE,PROC,VIRTUAL**

**TakeAccepted  PROCEDURE(),BYTE,PROC,VIRTUAL**

**            END**

**Viewer    AsciiViewerClass            !declare Viewer object**

**Searcher  AsciiSearchClass            !declare Searcher object**

**Printer   AsciiPrintClass             !declare Printer object**

** CODE**

** GlobalResponse = ThisWindow.Run()**

**ThisWindow.Init PROCEDURE()**

**ReturnValue   BYTE,AUTO**

** CODE**

** ReturnValue = PARENT.Init()**

** IF ReturnValue THEN RETURN ReturnValue.**

** SELF.FirstField = ?AsciiBox**

** SELF.VCRRequest &= VCRRequest**

** SELF.Errors &= GlobalErrors**

** OPEN(ViewWindow)**

** SELF.Opened=True**

** CLEAR(Filename)**

** ViewerActive=Viewer.Init(AsciiFile,A1:Line,Filename,?AsciiBox,GlobalErrors)**

** IF ~ViewerActive THEN RETURN Level:Fatal.**

** Viewer.AddItem(Searcher)               !register Searcher with Viewer**

** Viewer.AddItem(Printer)                !register Printer with Viewer**

** SELF.SetAlerts()**

** RETURN ReturnValue**

**ThisWindow.TakeAccepted PROCEDURE()**

**ReturnValue          BYTE,AUTO**

**  CODE**

**  ReturnValue = PARENT.TakeAccepted()**

**    CASE ACCEPTED()**

**    OF ?Print**

**      ThisWindow.Update**

**      IF ViewerActive THEN Viewer.Printer.Ask.  !display Print Options dialog**

**    OF ?Search**

**      ThisWindow.Update**

**      IF ViewerActive**

**       IF CHOICE(?AsciiBox)>0                   !search from current line**

**        Viewer.Searcher.Ask(Viewer.TopLine+CHOICE(?AsciiBox)-1)**

**       ELSE**

**        Viewer.Searcher.Ask(1)            !search from line 1**

**       END**

**      END**

**     END**

**    RETURN ReturnValue**