EECS 1012 Lecture Notes - Lecture 11: Regular Expression, Empty String, Pattern Matching

• School: York University
• Department: Electrical Engineering and Computer Science
• Course: EECS 1012
• Professor: Michael S. Brown

Document Summary

Lecture 11- javascript and forms (final lecture for 2018 because php lecture won"t be on exam) Javascript considers all expressions to be true, except the following: 0 (zero is considered false, but not "0") Nan (this happens in some math, e. g. 0/0;) false (of course-false is false) We have seen how to use alert to output messages. For debugging, you can also use the console object. Example: function myfunction() { var num1 = 5; if (num1==5) { console. log("num1 is equal to" + num1); A regular expression is a text string that defines a character pattern. You create a regular expression in javascript using the command var re = This syntax for creating regular expressions is sometimes referred to as a regular expression literal. We can use the regular expression variable re. test("some string") The method test() return true if the string contains the pattern. A string comparison has to be exact. Patterns can include characters (or character ranges) specified between brackets.