MyDAC

TMemDataSet.Locate Method

Searches a dataset by the fields specified by name for a specific record and positions the cursor on it.

Class

TMemDataSet

Syntax

function Locate(const KeyFields: string; const KeyValues: variant; Options: TLocateOptions): boolean; overload; override;

Parameters
KeyFields
Holds a semicolon-delimited list of field names in which to search.
KeyValues
Holds the variant that specifies the values to match in the key fields.
Options
Holds additional search latitude when searching in string fields.
Return Value
True if it finds a matching record, and makes this record the current one. Otherwise it returns False.

Remarks

Call the Locate method to search a dataset for a specific record and position cursor on it.

KeyFields is a string containing a semicolon-delimited list of field names on which to search.

KeyValues is a variant that specifies the values to match in the key fields. If KeyFields lists a single field, KeyValues specifies the value for that field on the desired record. To specify multiple search values, pass a variant array as KeyValues, or construct a variant array on the fly using the VarArrayOf routine. An example is provided below.

Options is a set that optionally specifies additional search latitude when searching in string fields. If Options contains the loCaseInsensitive setting, then Locate ignores case when matching fields. If Options contains the loPartialKey setting, then Locate allows partial-string matching on strings in KeyValues. If Options is an empty set, or if KeyFields does not include any string fields, Options is ignored.

Locate returns True if it finds a matching record, and makes this record the current one. Otherwise it returns False.

The Locate function works faster when dataset is locally sorted on the KeyFields fields. Local dataset sorting can be set with the TMemDataSet.IndexFieldNames property.

Example

An example of specifying multiple search values:

with CustTable do
   Locate('Company;Contact;Phone', VarArrayOf(['Sight Diver', 'P',
      '408-431-1000']), [loPartialKey]); 

See Also

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