Add a key to a custom built order.
XSharp.RT (in XSharp.RT.dll) Version: 2.2a
Syntax View Source
uOrder AS USUAL,
cIndexFile AS USUAL,
uKeyValue AS USUAL
) AS USUAL
public static Usual OrdKeyAdd(
[DefaultParameterValueAttribute(0, 1)] Usual uOrder,
[DefaultParameterValueAttribute(0, 1)] Usual cIndexFile,
[DefaultParameterValueAttribute(0, 1)] Usual uKeyValue
- Type: Usual
The name of the order or a number representing its position in the order list. Using the order name is the preferred method since the position may be difficult to determine using multiple-order index files. If omitted or NIL, the controlling order is assumed.
Specifying an invalid order, such as one that is not custom built, will raise a runtime error.
- Type: Usual
The name of an index file, including an optional drive and directory (no extension should be specified). Use this argument with <cOrder> to remove ambiguity when there are two or more orders with the same name in different index files.
If <cIndexFile> is not open by the current process, a runtime error is raised.
- Type: Usual
A specific key value that you want to add for the current record. The data type must match that of the order. If not specified, the order's key expression is evaluated for the current record and added to the order.
TRUE if successful; otherwise FALSE.
From the standard RDDs only the DBFCDX RDD supports Custom Indexes. This RDD does NOT support the use of the <uKeyValue> parameter. It always uses the Key Expression to calculate the Key Values to insert.
A custom built order is one that is not automatically maintained by the DBFCDX driver. You can determine if an order is custom built using DBOrderInfo(DBOI_CUSTOM, ...). When you create such an order, it is initially empty. You must manually add and delete keys using OrdKeyAdd() and OrdKeyDel().
OrdKeyAdd() evaluates the key expression (or <uKeyValue>, if specified), then adds the key for the current record to the order. If the order has a for condition, the key will be added only if that condition is met, and then, only if it falls within the current scoping range.
Note: RDDs may allow you to add several keys for the same record with consecutive calls to OrdKeyAdd().
OrdKeyAdd() will fail if:
The record pointer is positioned on an invalid record (i.e., at EOF())
The specified order is not custom built
The specified order does not exist
No order was specified and there is no controlling order
By default, this function operates on the currently selected work area. It can be made to operate on an unselected work area by specifying it within an aliased expression
This example creates a custom index and adds every fiftieth record to it:
USE customer VIA "DBFCDX"
// Create custom built order that is initially empty
INDEX ON LastName TO Last CUSTOM
// Add every 50th record
FOR n := 1 UPTO RecCount() STEP 50