Javascript Regular Expression exercises

<MCE: Script Type = "text/JavaScript"> <! -- <Br/> function f () {<br/> // var Reg = new Regexp ("cat "); <br/> // Example 1 <br/> // var Reg =/^ The/; // start with <br/> // var Reg =/Ere $ /; // end <br/> // var Reg =/her/; // contains <br/> // var S = "there "; <br/> // var r = S. match (REG); <br/> // If (R! = NULL) Alert ("Match successful"); <br/> // Example 2 <br/> // var Reg =/Th */; // 0 or more h after T <br/> // var Reg =/TH + /; // T plus one or more H <br/> // var Reg =/th? // 0 or 1 h after T <br/> // var Reg =/t? E + $/; // starts with 0 or 1, and ends with one or more E. <br/> // var S = "thered "; <br/> // Example 3 <br/> // var Reg =/Th {1 }/; // T has two H <br/> // var Reg =/Th {1 ,}/; // one or more h after T <br/> // var Reg =/Th {3, 5} e /; // 3 to 5 h after T <br/> // var S = "thhhered"; <br/> // var Reg =/Th (ERE) {1 ,} d/; // one or more ere <br/> // var Reg =/^ (Hi | The) [A-Z] * Ed $ /; // hi or the beginning, any letter in the middle, ending with Ed <br/> // var S = "thereered"; <br/> // var Reg =/gv. [0-9] //. represents any character <br/> // var S = "gv211"; <br/> // var re G =/[a-d]/; // lowercase between A and D <br/> // var S = ""; <br/> var Reg =/^ [A-Za-Z] $/; // any letter, one. <Br/> var S = "ad"; <br/> var r = S. Match (REG); <br/> If (R! = NULL) Alert ("Match successful"); <br/>}< br/> function F1 () {// practical example, determine the date format <br/> var Reg =/^ ([0-9] +)-([0-9] {1, 2 }) -([0-9] {1, 2}) ([0-9] {1, 2}) :( [0-9] {1, 2 }) :( [0-9] {}) $/; <br/> var r = "12:12:33 ". match (REG); <br/> If (R! = NULL) Alert ("OK"); <br/>}< br/> document. onclick = F1; </P> <p> // --> </MCE: SCRIPT>