Regular Expression exec, match, and test, execmatchtest

Regular Expression exec, match, and test, execmatchtest

Var patt = new RegExp (/\ d +/g); var str = "dfgdfg5465yhhgh65y65hh41"; var result; // var reset#patt.exe c (str ); while (result#patt.exe c (str ))! = Null) {// alert (patt. lastIndex) document. write (result); document. write ("<br/>"); document. write (patt. lastIndex); document. write ("<br/>");} document. write (str. match (patt); document. write (patt. test (str ));

Exec matches only once and returns the array format match. If there is a global match mode, g always matches to the end. Test returns boolean values true and false.

Therefore, a loop is required after all exec matches. Each time a regular object is matched, A lastIndex attribute will be returned, and the next time it is executed, it will start from lastindex and match it later. If no match exists, null is returned;

Match Method string method. Returns an array. Whether or not the matching depends on the global g flag.