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  • Filter
  • Filtered browse
  • Enabling/Disabling a filter
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Stored procedures
Defines and enables a "Contains" filter on a data file, view or query. The "Contains" filter is used to select all the records containing a specific set of characters.
This filter is not case sensitive.
This filter does not use any index, it browses the entire data file.
Example
SearchKey is string = Customer.FilterContains(Comments, "VIP")
Customer.ReadFirst(SearchKey)
WHILE NOT Customer.Out()
Trace(Customer.CustomerName, Customer.City)
Customer.ReadNext(SearchKey)
END
// Disables the filter
Customer.DeactivateFilter()
Syntax
<Result> = <Source>.FilterContains(<Item> , <Value>)
<Result>: Character string
Browse item. Corresponds to:
  • the name of item used to loop through the data file if the filter is enabled,
  • an empty string ("") if the filter cannot be implemented.
<Source>: Type corresponding to the specified source
Name of the HFSQL data file, view or query used.
<Item>: Character string
Name of item on which the filter will be implemented. This item can be a key item or a non-key item.
<Value>: Character string
Value that must be found in the record item.
Remarks

Filter

  • The filter is enabled as soon as <Source>.FilterContains is called.
  • Equivalent syntaxes:
    FileName.FilterContains(ItemName, "Value")

    is equivalent to:
    FileName.Filter("ItemName ~]'Value'")

Filtered browse

When a filter is defined and enabled on a data file, any record read corresponds to the filter. If no other record corresponds to the filter during the iteration:
  • <Source>.Out returns True.
  • the current record corresponds to the last record read with the filter.
For example:
On a filtered data file, after the function:the current record is:
<Source>.ReadFirstthe first file record corresponding to the filter.
<Source>.ReadLastthe last file record corresponding to the filter.
<Source>.ReadNext (or <Source>.Forward)the next record (or the next nth record) corresponding to the filter.
<Source>.ReadPrevious (or <Source>.Backward)the previous record (or the previous nth record) corresponding to the filter.

Enabling/Disabling a filter

  • <Source>.DeactivateFilter is used to disable a filter.
  • <Source>.ActivateFilter is used to re-enable a filter.
  • The filter is deleted when the data file (query or view) is closed (<Source>.Close or HOpenAnalysis for example).
  • A single filter can exist at a given time on a data file (query or view). If <Source>.FilterContains is used several times, only the last filter will be taken into account: the previous filters will be deleted. Similarly, if several filters are used (HFilter* functions), only the last filter will be taken into account.
Component: wd290hf.dll
Minimum version required
  • Version 25
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Last update: 07/06/2023

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