jquery Basic selector (. Class selector)

//Match elements with class attribute values
<!DOCTYPE HTML Public "-//W3C//DTD XHTML 1.0 transitional//en" "http://www.w3.org/TR/xhtml1/DTD/ Xhtml1-transitional.dtd "><HTMLxmlns= "http://www.w3.org/1999/xhtml"> <Head>  <title>. class Selector</title>  <Metahttp-equiv= "Content-type"content= "Text/html;charset=utf-8" />  <styletype= "Text/css">. Class1{Color:Red;}  </style>  <Scripttype= "Text/javascript"src= "Jquery-1.7.1.min.js"></Script>  <Scripttype= "Text/javascript">window.onload=function() {document.getElementById ('Btnok'). onclick=function(){                $('. Class1'). HTML ('PHP'); //match elements that use. Class1 and replace content            };  }; </Script> </Head> <Body>  <DivID= "Div1">Div1</Div>  <HR/>  <Divclass= "Class1">Div2</Div>  <HR/>  <Pclass= "Class1">Yang</P>  <inputtype= "button"ID= ' Btnok 'value= ' OK '/> </Body></HTML>

jquery Basic selector (. Class selector)