In many sites this is a very common effect, is to click on the general category of the check box, automatically select all subcategories of the check box, or if all the sub categories are all check boxes are selected, the General category check box is also automatically selected.
This time I was on MSN's website on the chance to see, so I also tried to write down.
<! DOCTYPE HTML PUBLIC "-//W3C//DTD XHTML 1.0 transitional//en" "Http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd "> <ptml xmlns=" http://www.w3.org/1999/xhtml "xml:lang=" en "lang=" en "> <pead> <title></titl e> <script type= "Text/javascript" > Function Checkall (str) {var A=document.getelementbyid ("T" +str ). getElementsByTagName ("input"); var B=document.getelementbyid ("D" +str); for (Var i=0;i<a.length;i++) {a[i].checked=b.checked; } function Fixchk (str) {var A=document.getelementbyid ("T1"). getElementsByTagName ("input"); var B=document.getelementbyid ("D1"); for (Var i=0;i<a.length;i++) {if (a[i].checked==false) {b.checked=false; return; }} b.checked=true; } </script> </pead> <body> <center> <div ><input type= "checkbox" id= "D1" onclick= "Checkall (' 1 ')"/> Entertainment </div> <div id= "T1" > <input type= "checkbox" onclick= "Fixchk (' 1") "/> books and magazines <input type=" checkbox "onclick=" Fixchk (' 1 ') "/> Music and DVD <input type= "checkbox" onclick= "Fixchk (' 1 ')"/> Travel </div> </center> </body> </ptml>
[Ctrl + A All SELECT Note: If the need to introduce external JS need to refresh to perform]
