getElementsByTagName与getElementsBytagname
function selall()
{
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;
}
}
</script>
有区别？JS是强语法吗？{
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;
}
}
</script>
上面红色代码改为getElementsBytagname则函数动作无效
