Difference between revisions of "locate"
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Search options can be | Search options can be | ||
* loCaseInsensitive: ignore upper case/lower case differences when searching | * loCaseInsensitive: ignore upper case/lower case differences when searching | ||
| − | * loPartialKey: match partial finds (instead of the complete key) | + | * loPartialKey: match partial finds (instead of the complete key). Note: this only works for string-type fields, not for number/date/currency etc fields where this option is ignored. |
{{Note|Locate is only implemented in non-unidirectional datasets, i.e. you must be able to move back and forwards through the dataset.}} | {{Note|Locate is only implemented in non-unidirectional datasets, i.e. you must be able to move back and forwards through the dataset.}} | ||
Revision as of 08:39, 19 December 2012
Definition
Unit: FreePascal, unit db
function Locate(const KeyFields: string; const KeyValues: Variant; Options: TLocateOptions): Boolean; override;Official documentation: none
Description
locate looks for a record in the dataset where the specified search values for the specified fields match. If found, the function returns true and the cursor position/current record moves to that record.
KeyFields can be a single field name or a semicolon-separated list of fields.
KeyValue can be a variant or a variant array and the number of items must match the number of fields specified in KeyFields.
Search options can be
- loCaseInsensitive: ignore upper case/lower case differences when searching
- loPartialKey: match partial finds (instead of the complete key). Note: this only works for string-type fields, not for number/date/currency etc fields where this option is ignored.
Note: Locate is only implemented in non-unidirectional datasets, i.e. you must be able to move back and forwards through the dataset. Note: Locate and lookup act at low level inside a dataset to search for records. Often it is more efficient to filter/limit what gets into the dataset in the first place, e.g. using SQL WHERE clauses.Example
// Using a TDBF dataset
uses dbf, db
...
// Look for 'di Angelo', 'Di Angelo' etc in a field called
// LASTNAME
if MyDBF.Locate('LASTNAME','di Angelo',[loCaseInsensitive])then
writeln('Found record.');See also
- [1] Description of how to use locate with Delphi
