Srch

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The Srch internal function searches an array and returns the row number matching the argument. If the argument is not found, then either 0 (BR 4.1 and below) or -1 (BR 4.2 and above). The argument must be the same data type (string or numeric) as the array. The optional "row" parameter defines the starting array element for the search.

SRCH(<array-name>,<argument>[,<row>])

OR

SRCH(<array-name$>,[^]<argument$>[,<row>])

Optional Case Insensitivity and Substring matching

If argument$ begins with the caret ^, then the ^ is stripped and the search for argument$ in array-name$ becomes case insensitive (as of 4.2). Also, when the caret ^ is specified, the search is performed for sub-strings instead of whole strings.

For example:

00010 let a$(1)='abc'
00020 let a$(2)='def'
00030 print srch(mat a$,'^B')

Output:

1

Given the (4.2+) SRCH use of the "^" character, to search for '^' with "let X=POS(string$,'^',5)" you will need to either turn the search character off with CONFIG SEARCH_CHAR OFF or replace the search character with something else as in CONFIG SEARCH_CHAR 7E (where 7E is the hexadecimal representation of an alternate search character).

Comments and Examples

As of 4.2, SRCH returns zero if it fails (instead of -1) unless OPTION BASE ZERO is in effect or OPTION 56 is in effect.

For versions 4.1 and earlier, when the search is unsuccessful, Srch returns -1. Using OPTION BASE 0 will also cause SRCH to return a zero.

In line 510 below, if STATES$ is a string array containing the 50 valid two-letter state abbreviations, then a data entry program could check whether the operator entered a correct abbreviation into the variable ST$ by the following:

500 LINPUT ST$
510 If Srch(Mat States$,ST$) = 0 then goto 500

The example below will find the selected item in a combo box

500 combo_choice$=srch(mat array-name$,"^^")

IMPORTANT

Earlier versions of BR return 0 when SRCH doesn't find the desired argument in the array. Later versions return -1 in the same situation. In order to make you programs produce the same results regardless of the BR version, use the following logic:

00010 if not SRCH(mat array$, string_to_find$) > 0 then
00020    ! add the code for when the result is NOT found
00030 else
00040    ! add the code for when the result IS found
00050 end if

Related Functions

Technical Considerations

  1. If a match was not found, Srch will return -1.