TDataSet.Filter Property

Specifies the text of the current filter for a dataset.

Pascal

property Filter: string;

C++

__property AnsiString Filter;

Description

Use Filter to specify a dataset filter. When filtering is applied to a dataset, only those records that meet a filter's conditions are available. Filter describes the filter condition. For example, the following filter condition displays only those records where the State field is 'CA' or 'MA':

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State = 'CA' or State = 'MA'

When a filter is set, Blank records do not appear unless explicitly included in the filter. For example:

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State <> 'CA' or State = NULL

When a field name contains spaces, you must enclose the field name in brackets. For example:

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[Home State] = 'CA' or [Home State] = 'MA'

Filter expressions on remote SQL tables and on client datasets support field comparisons. For example:

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Field1 > Field2

Field comparisons are not supported against local tables (Paradox, dBASE, Access, FoxPro).

For a complete list of operators you can use in filter strings, see SettingTheFilterProperty.

Note: Filters are not supported on unidirectional datasets. If you set the Filter property of a unidirectional dataset, it raises an exception.

The FilterOptions property controls case sensitivity and filtering on partial comparisons.

Tip: Applications can set Filter at runtime to change the dataset's filtering condition (for example, in response to user input).