Modifying a Range

From RAD Studio
Jump to: navigation, search

Go Up to Limiting Records with Ranges


Two functions enable you to modify the existing boundary conditions for a range: EditRangeStart, for changing the starting values for a range; and EditRangeEnd, for changing the ending values for the range.

To edit and apply a range:

  1. Putting the dataset into dsSetKey state and modifying the starting index value for the range.
  2. Modifying the ending index value for the range.
  3. Applying the range to the dataset.

You can modify either the starting or ending values of the range, or you can modify both boundary conditions. If you modify the boundary conditions for a range that is currently applied to the dataset, the changes you make are not applied until you call ApplyRange again.

Editing the start of a range

Call the EditRangeStart procedure to put the dataset into dsSetKey state and begin modifying the current list of starting values for the range. Once you call EditRangeStart, subsequent assignments to the Fields property overwrite the current index values to use when applying the range.

Tip: If you initially created a start range based on a partial key, you can use EditRangeStart to extend the starting value for a range.

Editing the end of a range

Call the EditRangeEnd procedure to put the dataset into dsSetKey state and start creating a list of ending values for the range. Once you call EditRangeEnd, subsequent assignments to the Fields property are treated as ending index values to use when applying the range.

See Also