? - Question MarkThe question mark symbol ? matches zero or one occurrence of the pattern left to it.ExpressionStringMatched? ma?n mn 1 match man 1 match maaan No match (more than one a character) main No match (a is not followed by n) woman 1 match...
\$amatch if a string contains$followed bya. Here,$is not interpreted by a RegEx engine in a special way. If you are unsure if a character has special meaning or not, you can put\in front of it. This makes sure the character is not treated in a special way. Special Sequences Speci...
\ Backslash Escapes the following character, treating metacharacters as literals or giving special meaning to ordinary characters \. matches a literal dot, \d matches any digit ? Question mark Makes the preceding character or group optional, matching it zero or one time colou?r matches both “co...
Question mark ?– It is used to match the preceding character 0 or more times meaning it is optional. For instance, the expression ^https? would mean that the URLs must start with http and they can be either http or https. It can also turn greedy matches into lazy ones when used with...
The question mark (?) This symbol means “optional” or “the pattern to my left might or might not exists”. /colou?r/would match bothcolorandcolourin a given string because?makesuoptional. It also has another meaning. If placed before another set of instructions, it will make it less...
The question mark (?) quantifier matches zero or one occurrences of the preceding character or group. The curly braces ({}) quantifier allows you to specify an exact number of occurrences of the preceding character or group. Character Classes Character classes are a way to match a set of cha...
2.3.3 The Question Mark In regular expressions, the meta character?makes the preceding character optional. This symbol matches zero or one instance of the preceding character. For example, the regular expression[T]?hemeans: Optional uppercaseT, followed by a lowercaseh, followed by a lowercasee...
2.3.3 The Question MarkIn regular expressions, the meta character ? makes the preceding character optional. This symbol matches zero or one instance of the preceding character. For example, the regular expression [T]?he means: Optional uppercase T, followed by a lowercase h, followed by a ...
Question Mark (?):The question mark is a metacharacter representing zero or one occurrence of the preceding element. To match a literal question mark, escape it with a backslash (\?). Curly Braces ({}):Curly braces are used for quantifiers to specify the number of occurrences. To match ...
8. Question Mark (?) The question mark is used as a qualifier to check for zero or one occurrence of the preceding character. Using this means that the last character is optional, and it is useful if you want to target misspellings. For example: shoes? would match shoe or shoes, bu...