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instr, instr$   function


Syntax
foundPosition = instr( startPos, targetCFString, searchCFString [, searchOptions] )
foundPosition = instr$( startPos, targetPascalString or targetContainer$$, searchPascalString or searchContainer$$)

Description
This function searches for the first occurrence of searchCFString, searchPascalString or searchContainer$$ within targetCFString, targetPascalString or targetContainer$$, starting at character position startPos. The string search is case-sensitive by default, but see searchOptions parameter in instr syntax.

 
instr parameters
Parameter
 Description
startPos The character position to start the search.
If startPos is less than 0, it's treated as 0 for a forward search, and the last character for a backward search.
targetString The string to search.
searchString The string to search for. If the NSRegularExpressionSearch search option is used, this is the regex pattern.
searchOptions Search options can be combined using '+':
NSCaseInsensitiveSearch
NSLiteralSearch
NSBackwardsSearch
NSAnchoredSearch
NSNumericSearch
NSDiacriticInsensitiveSearch
NSWidthInsensitiveSearch
NSForcedOrderingSearch
NSRegularExpressionSearch N.B. If this option is set, no other options can apply except NSCaseInsensitiveSearch and NSAnchoredSearch.
 
instr return value
If a match is found, the function returns the character position where the match begins. If no match is found, returns NSNotFound.

instr example
CFStringRef string, searchString

string = @"An I for an i and a tooth for a tooth"
searchString = @"i"

print instr( 0, string, searchString )
print instr( 0, lcase(string), lcase(searchString) )
print instr( 0, string, searchString, NSCaseInsensitiveSearch )
print instr( 22, string, searchString, NSBackwardsSearch )// searches backwards from character 22 to 0
print instr( 0, string, @"[aeiou]", NSRegularExpressionSearch ) // returns position of first, lowercase vowel in string

HandleEvents

 
instr$ parameters
Parameter
 Description
startPos The character position to start the search. If startPos is less than 1, it's treated as 1.
targetString The string to search.
searchString The string to search for.
 
instr$ return value
If a match is found, the function returns the character position where the match begins. If no match is found, returns 0.

 
See also
indexf; mid; left; right