We need subexpressions for complex and refined output. We can refine our output by grouping the expressions. E.g. Test Case – HelloHello RegEx – Hello{2,} Result – Hello{2,} It will not match any Hello because above expression is finding 'Hell' and atleast two occurence of 'o'. So, we need to create Read more…
Using Boundaries : Position matching is used to specify where within a string of text a match should occur. To understand the need for position matching,consider the following example: TEXT The cat scattered his food all over the room. REGEX cat RESULT The cat scattered his food all over the Read more…
Matching One or More Characters To match one or more instances of a character (or set),simply append a + character. + matches one or more characters (at least one; zero would not match). Whereas a matches a, a+ matches one or more as. Similarly, whereas [0-9] matches any digits, [0-9]+ Read more…
Escaping : Metacharacters are characters that have special meaning within regular expressions. The period (.) is a metacharacter; it is usedto match any single character. Similarly, the left bracket ([) is a metacharacter; it is used to mark the beginning of a set. Because metacharacters take on special significance when Read more…