< meta charset ="UTF-8" > < link type ="text/css" href ="09.css" rel ="stylesheet" /> < script type ="text/javascript" src ="jquery.js" ></ script > < title ></ title > </ head > < h1 > wo men </ h1 > < p > cfjdsmc edvc ewrd csd wrvc d 2e34efrew8r934efc cred ewfced vefwid cfer fd 3ew fcxdwdkjfdke fewf dewkdse fcedwfewdfcs fre dfc ed fcejfoklew ferf defedefcd </ p > < input type ="button" id ="big" value ="放大" />< br /> < input type ="button" id ="small" value ="缩小" /> < script type ="text/javascript" > $( " input " ).click( function (){ var t = $( " p " ).css( " font-size " ) var t1 = parseInt(t, 10 ) var unit = t.slice( - 2 ) var name1 = $( this ).attr( " id " ) if (name1 == " big " ){ t1 += 2 else if (name1 == " small " ){ t1 -= 2 $( " p " ).css( " font-size " , t1 + unit) </ script > </ body > </ html >