The XLATE function will return the data value of a field, given the name of the file, the record key, the field number, and an action code. It takes the general form:
XLATE ([DICT] filename, key, field#, action.code)
DICT is the literal string to be placed before the file name in the event it is desired to open the dictionary portion of the file, rather than the data portion.
filename is a string containing the name of the file to be accessed. Note that it is the actual name of the file, and not a file unit variable. This function requires the file name, regardless of whether or not the file has been opened to a file unit variable.
key is an expression that evaluates to the record key, or item ID, of the record from which data is to be accessed.
field# is the field number to be retrieved from the record.
action.code indicates the procedure if the field is null, or cannot find the if record. This is a literal, which may be:
|X||Returns a null string. This is the default action|
|V||Prints an error message.|
|C||Returns the value of key|
If the field being accessed is a dynamic array, XLATE will return the array with the delimiter characters lowered by 1. For example, multivalue marks (ASCII-253) are returned as subvalue marks (ASCII-252), and subvalue marks are returned as text marks (ASCII-251). If supplied -1 for field#, it returns the entire record.
Examples of use include:
1. Retrieval of a simple field: Given a file called "VENDORS" containing a record with the record key of "12345" and which contains the value of "ABC Company" in field 1,
VENDOR.ID = "12345" VENDOR.NAME = XLATE("VENDORS",VENDOR.ID,1,"X") CRT VENDOR.NAME
to display: ABC Company
2. Retrieval of an array: Suppose field 6 of the VENDORS file contains a multivalued list of purchase order numbers, such as
10011]10062]10079 use the XLATE function to retrieve as :
PO.LIST = XLATE("VENDORS",VENDOR.ID,6,"X") CRT PO.LIST
to display: 10011\10062\10079
Notice that the backslashes (\) were substituted for brackets (]), indicating that the delimiter is now CHAR(252).
3. Retrieval of an entire dictionary item: Given a dictionary item called "VENDOR.NAME" with the following content:
001 A 002 1 003 Vendor Name 004 005 006 007 008 009 L 010 30
using the statements:
DICT.ID = "VENDOR.NAME" DICT.REC = XLATE("DICT VENDORS",VENDOR.ID,-1,"C") PRINT DICT.RECwill display
to display: A]1]Vendor Name]]]]]L]30
See also: TRANS.
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