<script language="javascript">
function chk(){
var num=3;
for (var i=1;i<=num;i++)
{
if(document.all["zdm"]+i){
if (document.form1.zdm+i.value=="")
{
alert("请输入值!");
return;
document.form1.zdm+i.focus();
document.form1.zdm+i.select();
}
}
}
}
</script>
function chk(){
var num=3;
for (var i=1;i<=num;i++)
{
if(document.all["zdm"]+i){
if (document.form1.zdm+i.value=="")
{
alert("请输入值!");
return;
document.form1.zdm+i.focus();
document.form1.zdm+i.select();
}
}
}
}
</script>
alert("hehe");
}
<body>
<form id="form1">
<input type="text" name="zdm1" id="zdm1" size="20">
<input type="text" name="zdm2" size="20">
<input type="text" name="zdm3" size="20">
<input type="text" name="zdm4" size="20">
<input type="text" name="zdm5" size="20">
</form>
<input type="button" onclick="aaaa()">
</body>
<script>
function aaaa(){
var num=5;
//alert(form1.zdm1.value)
for (var i=1;i<=num;i++)
{
DD = "form1.zdm"+i
alert(eval(DD).value)
if (DD.value=="")
{
alert("请输入值!");
document.form1.zdm+i.focus();
document.form1.zdm+i.select();
return;
}
} }
</script>
</html>
<body>
<form id="form1">
<input type="text" name="zdm1" id="zdm1" size="20">
<input type="text" name="zdm2" size="20">
<input type="text" name="zdm3" size="20">
<input type="text" name="zdm4" size="20">
<input type="text" name="zdm5" size="20">
</form>
<input type="button" onclick="aaaa()">
</body>
<script>
function aaaa(){
var num=5;
//alert(form1.zdm1.value)
for (var i=1;i<=num;i++)
{
DD = eval("form1.zdm"+i)
alert(DD.value)
if (DD.value=="")
{
alert("请输入值!");
DD.focus();
DD.select();
return;
}
} }
</script>
</html>