复制代码 代码如下: <script language=javascript> //第一种方法 function selectall1() { var a = document.getElementsByTagName("input"); if(a[0].checked==true){ for (var i=0; i<a.length; i++) if (a[i].type == "checkbox") a[i].checked = false; } else { for (var i=0; i<a.length; i++) if (a[i].type == "checkbox") a[i].checked = true; } }
//第二种方法
function selectall2() { var tform = document.forms['form1']; for (var i=0;i<tform.length;i++) { var e = tform.elements[i]; if (e.type == "checkbox") e.checked = !e.checked; } }
//第三种方法,结合上述两种方法 function selectall3() { var a = document.getElementsByTagName("input"); for (var i=0; i<a.length; i++) if (a[i].type == "checkbox") a[i].checked =!a[i].checked; } //第四种方法 function selectall4(id){ //用id区分 var tform=document.forms['form1']; for(var i=0;i<tform.length;i++){ var e=tform.elements[i]; if(e.type=="checkbox" && e.name==id) e.checked=!e.checked; } } //第五种方法 function selectall(theform,thename){ //theform指定的form,thename是checkbox的name属性 var tform=document.forms[theform]; document.getElementById("thewen").value='反选'; for(var i=0;i<tform.length;i++){ var e=tform.elements[i]; if(e.type=='checkbox' && e.name==thename)e.checked=!e.checked; } } </script> <form id="form1" name="form1" method="post" action=""> <input type="checkbox" name="sid" value="1" /> <input name="thes" type="button" onclick="javascript:selectall3()" value="全选" /> </form>