Find index key (indexedField; value) Longint
|indexedField||Field||Indexed field on which to execute the search|
|value||Field | Variable||Value to search|
|Function result||Longint||Number of the record found or|
|-1 if no record was found|
The Find index key command returns the number of the first record whose indexedField field is equal to value.
If no records are found, Find index key returns -1.
After calling this command, value contains the value found. This feature allows you to execute searches using the wildcard character ("@") on Alpha fields and then retrieve the value found.
This command doesn't modify the current selection or the current record.
This command is fast because it only uses the index, and is particularly useful to avoid creating double entries during data entry.
In an audio CD database, during data entry let's assume that you want to verify the singer's name to see if it already exists in the database. Because homonyms can exist, you don't want the [Singer]Name field to be unique. Therefore, in the input form, you can write the following code in the [Singer]Name field's object method:
If (Form event=On Data Change) $RecNum:=Find index key([Singer]Name;[Singer]Name) If ($RecNum # -1) ` If this name has already been entered CONFIRM("A singer with the same already exists. Do you want to see the record?";"Yes";"No") If (OK=1) GOTO RECORD([Singer];$RecNum) End if End if End if