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As an aid to understanding the ASCIIViewerClass, it is useful to organize the its methods into two large categories according to their expected use--the primary interface and the virtual methods. This organization reflects what we believe is typical use of the ASCIIViewerClass methods.

**Non-Virtual Methods**

The Non-Virtual Methods, which you are likely to call fairly routinely from your program, can be further divided into three categories:

**Housekeeping (one-time) Use:**

|  | Init | initialize the ASCIIViewerClass object |
|  | Kill | shut down the ASCIIViewerClass object |

**Mainstream Use:**

|  | AskGotoLine | go to user specified line |
|  | DisplayPage | display new page |
|  | PageDown | scroll down one page |
|  | PageUp | scroll up one page |
|  | TakeEvent | process ACCEPT loop event |

**Occasional Use:**

|  | AddItem | add printer or searcher object |
|  | GetFilename(i) | return the filename |
|  | GetLastLineNo(i) | return last line number |
|  | GetLine(i) | return line of text |
|  | GetPercentile(i) | convert file position to percentage |
|  | Reset | reset the ASCIIViewerClass object |
|  | SetPercentile(i) | convert percentage to file position |
|  | SetLine(v) | position to specific line |
|  | SetLineRelative | move N lines |

**(i)These methods are inherited from the ASCIIFileClass.**

**(v) These methods are also virtual.**

**Virtual Methods**

Typically you will not call these methods directly--the Non-Virtual Methods call them. However, we anticipate you will often want to override these methods, and because they are virtual, they are very easy to override. These methods do provide reasonable default behavior in case you do not want to override them.

|  | FormatLine | format text |
|  | SetLine | position to specific line |
|  | ValidateLine | implement a filter |

These methods are inherited from the ASCIIFileClass.