WolframLang: String Replace

search, test, pattern matching

These functions take a String pattern (regex) .

StringStartsQ

StringStartsQ

StringEndsQ

StringEndsQ

StringMatchQ

StringMatchQ

StringContainsQ

StringContainsQ[ "some thing", "th" ]

StringContainsQ

StringFreeQ

StringFreeQ

StringPosition

StringPosition

StringCount

Count occurance StringCount

Get Substring by Pattern

StringCases

Get substring, by String pattern (regex) . Return a List . StringCases

(* extract email address *)

x = "emails john@gmail.com and mary441@yahoo.com etc";

StringCases[
 x,
 RegularExpression[ "[a-z0-9]+@[a-z0-9]+\\.com" ],
 IgnoreCase -> True] === {"john@gmail.com", "mary441@yahoo.com"}

String Replace

StringReplace

replace string by String pattern (regex) . StringReplace

StringReplace[ "some dogs" , {"dog" -> "cat"}] === "some cats"

StringReplacePart

replace string by position. StringReplacePart

StringReplacePart[ "some dogs", "cat", {6, 8}] === "some cats"