Undelete Record function

[csda1]

Here's my current version of an Undelete UDF (User-Defined Function). It is shown below and as an attached zip file.

Note that it exits early if all records have been undeleted or if there are no records to undelete. Also there are optional filters and record # ranges, and an option to mark or not the undeleted records.

Regards,

Ira J. Perlow
Computer Systems Design & Associates
[email protected]

function UndeleteRecords as N(TableName as C,Options as C,Filter as C)
' Created by Computer Systems Design & Associates
' Copyright 2001 Computer Systems Design & Associates, All Rights Reserved
' Last Update: June 15, 2001

' Input: TableName	= Table (dbf) name to delete.  
'							  If Null, it then prompts you for tables in the current database
'							  If blank (but not null), it uses the current table
'							  If "*", It prompts you for any table
'			Options		= "I" - Display information before running with choice to cancel
'							  "M" - Mark records that were undeleted
'							  "R" - Prompt for record range
'							  "F" - Prompt for filter
'								if null, then IRM options are selected
'			Filter		= Filter (in context of table) expression to process undelete for
'							  If blank or null, all records will be processed
'							  The filter expression may not be able to access the table fields unless
'							  the current form's table is used

' Output:	Number of records that were undeleted
'				Negative number indicates error

' Errors:	-1 = Cancelled operation
'				-2 = Table name not found
'				-3 = Table not available
'				-4 = Other errors

' Typical Usage:
'		Place a button on table to delete records with a function call like the example in it's code

' Examples:
'		UndeleteRecords("tablename","IRM","")

' Notes: 
'	The filter expression may not be able to access the table fields unless
'	the current form's table is used

' Set default error return
UndeleteRecords=-4

If Options=="" 
	Opt="IRM"
ELSE
	Opt=trim(Options)
End If

' If not blank and not asterisk, use the supplied tablename
IF .NOT.(TRIM(TableName)=="").AND..NOT.(ALLTRIM(TableName)=="*")
	' If file does not exist, then return
	IF .not.:File.Exists(TableName)
		UndeleteRecords=-2
		END
	END IF
	' Use the supplied Tablename
	TabNam=TableName
else if TableName==""
	dim tlist[100] as C
	tname=:A5.table_enum("")

	IF .NOT.(trim(tname)=="")
		' While the table_enum method returns 
		' nonblank names, get next name
		i=1
		WHILE .not.(trim(tname)=="")
			tlist[i]=tname
			i=i+1
			tname=:A5.table_enum(tname)
		END WHILE
		' sort the array otherwise names will be in 
		' order in which operations were created.
		sort_array("tlist")
		' Show the user a list of names
		choice=ui_get_list_array("Select Table to Undelete",1,"tlist")
		' If the user selects a table, then do it
		IF TRIM(choice)==""
			UndeleteRecords=-1
			END
		END IF
		getpath=IF(trim(:A5.Get_Master_Path())=="",:A5.Get_Path(),:A5.Get_Master_Path())
		IF .NOT.:File.Exists(getpath+chr(92)+choice+".dbf")
			UndeleteRecords=-2
			END
		END IF
		TabNam=getpath+chr(92)+choice+".dbf"
	END IF
ELSE IF TRIM(TableName)=="" 
	TabNam=table.current().Name_Get()+".dbf"
ELSE
	choice=ui_get_file("Table to Undelete Records:","Table(*.dbf)",table.current().Name_Get()+".dbf","X")
	IF TRIM(choice)==""
		UndeleteRecords=-1
		END
	END IF
	TabNam=choice
END IF
'trace.writeln("Table selected="+TabNam)

' Save status of table being opened
IF :Table.IsOpen(TabNam)
	opened=1
ELSE
	opened=0
END IF

' Set Flag to trap errors
ErrFlag=0
ON ERROR GOTO error_handler
tbl=table.open(TabNam)
ON ERROR GOTO 0

' If error in opening file, then exit with error
IF  ErrFlag=1
	UndeleteRecords=-3
	END
END IF 

' Counts of Regular and deleted records
reccnt=tbl.records_get()
recdel=tbl.records_deleted()

IF "I" $ UPPER(Opt)
	txt="Table: "+tabnam+CHR(10)+CHR(13)
	txt=txt+"  Total Records: "+STR(reccnt+recdel,7,0)+CHR(10)+CHR(13)
	txt=txt+"Deleted Records: "+STR(recdel,7,0)
	choicen=ui_msg_box("Undelete Records?",txt,UI_OK_CANCEL+UI_QUESTION_SYMBOL+UI_SECOND_BUTTON_DEFAULT)
	IF .not.(UI_OK_SELECTED=choicen)
		UndeleteRecords=-1

		' If the table was previously closed, close it now
		IF opened=0
			tbl.close() 
		END IF

		END
	END IF
END IF

' Exit if nothing to do
IF recdel=0
	UndeleteRecords=0
	END 
END IF

IF "F" $ UPPER(Opt)
	IF trim(filter)=="" 
		dflt=".T."
	ELSE
		dflt=alltrim(filter)
	END IF
	choice=ui_get_expr("Enter Filter Expression","Filter:",dflt)
	IF TRIM(choice)==""
		UndeleteRecords=-1

		' If the table was previously closed, close it now
		IF opened=0
			tbl.close() 
		END IF

		END
	END IF
	filtexp=alltrim(choice)
ELSE
	IF trim(filter)=="" 
		dflt=".T."
	ELSE
		dflt=alltrim(filter)
	END IF
	filtexp=dflt
END IF

IF "R" $ UPPER(Opt)
	choice=ui_get_number("Record Range for Undelete","Max Record="+LTRIM(STR(reccnt+recdel))+"   Begin Record #:","1")
	IF (0>=VAL(choice)).or.(VAL(choice)>reccnt+recdel)
		UndeleteRecords=-1

		' If the table was previously closed, close it now
		IF opened=0
			tbl.close() 
		END IF

		END
	END IF
	rangebeg=VAL(choice)

	choice=ui_get_number("Record Range for Undelete","Max Record="+LTRIM(STR(reccnt+recdel))+"     End Record #:",LTRIM(STR(reccnt+recdel)))
	IF (0>=VAL(choice)).or.(VAL(choice)>reccnt+recdel).or.(rangebeg>VAL(choice))
		UndeleteRecords=-1

		' If the table was previously closed, close it now
		IF opened=0
			tbl.close() 
		END IF

		END
	END IF
	rangeend=VAL(choice)
ELSE
	rangebeg=1
	rangeend=reccnt+recdel
END IF

Undeleted=0

i=1
' Get pointer to delete/mark field
' Field contains "-" (Dash) for Marked, "*" (Asterick) for Deleted,
'	 " " (space) for regular record
fld=tbl.field_get(0)

i=rangebeg
ON ERROR GOTO error_handler

nxt:

	tbl.fetch_goto(i)
	IF tbl.is_deleted()
		tbl.change_begin()
		ErrFlag=0
		fil=eval(filtexp)
		IF ErrFlag=1
			fil=.T.
			'trace.writeln("rec #="+LTRIM(STR(i))+"default")
		ELSE
			'trace.writeln("rec #="+LTRIM(STR(i))+"  filter="+IF(fil,".T.",".F."))
		END IF
		IF eval(filtexp)
			IF "M" $ UPPER(Opt)
				' Mark record
				tbl.mark()
				' Alternative way to do the mark
				'fld.value_put("-")
			ELSE
				' Undelete record
				fld.value_put(" ")
			END IF
			Undeleted=Undeleted+1
		END IF

		tbl.change_end(.t.)
	END IF
	i=i+1
' If some records still deleted and range has not yet been reached, repeat
IF rangeend>=i.and.recdel>Undeleted
	GOTO nxt 
END IF

ON ERROR GOTO 0

' New counts of Regular and deleted records
newcnt=tbl.records_get()
newdel=tbl.records_deleted()

' If the table was previously closed, close it now
IF opened=0
	tbl.close() 
END IF

UndeleteRecords=Undeleted

ui_msg_box("Undelete Results","Undeleted "+LTRIM(STR(Undeleted))+" records in table"+CHR(10)+CHR(13)+tabnam,UI_OK+UI_INFORMATION_SYMBOL)
 
END

' Error handler
error_handler:
ErrFlag=1
'errcode=error_code_get()
'errmsg=error_text_get(err)
RESUME NEXT

END

end function

[Wanda Tucker]

RE: Undelete Record function

Smarty pants. Just kidding! i am humbly educated, now, and will save your instructions for future use!
Thanks,
Wanda