I
Itai
I am attempting to create an ASP.NET Custom Validator javascript for a
checkboxlist control. My goal is to limit the total number of
selections to be 1 - 5 at most. My problem is that I get a null
reference when I attempt to retrieve an object for an individual list
item, which of course results
in an "object required" error message.
Anyone know what to do? tnx in advance
-Itai.
Here is the code:
<HEAD>
....
<script language="JavaScript">
function ChkMusicTasteSelection(source, arguments) {
var t = 0;
for(var i = 0; i < 31; i++) {
var chkbx = document.all.item("musicTaste_" + i);
// document.write(chkbx) --> null (getElementById() produces the
same effect)
if(chkbx.checked == true){
t++;
}
}
if((t <= 5) && (t >= 1)) {
arguments.IsValid = true;
}
else {
arguments.IsValid = false
}
}
}
</script>
</HEAD>
<body>
<form id="Form1" method="post" runat="server">
...
<TD style="HEIGHT: 188px"><asp:checkboxlist id="musicTaste"
runat="server"
Width="640px" RepeatColumns="5" RepeatDirection="Horizontal">
<asp:ListItem Value="1">60's</asp:ListItem>
<asp:ListItem Value="2">70's</asp:ListItem>
<asp:ListItem Value="3">80's</asp:ListItem>
...
Rendered Output: (browser ie6sp1)
<TD style="HEIGHT: 188px"><table id="musicTaste" border="0"
style="width:640px;">
<tr>
<td><input id="musicTaste_0" type="checkbox" name="musicTaste:0"
/><label for="musicTaste_0">60's</label></td>
<td><input id="musicTaste_1" type="checkbox" name="musicTaste:1"
/><label for="musicTaste_1">70's</label></td>
<td><input id="musicTaste_2" type="checkbox" name="musicTaste:2"
/><label for="musicTaste_2">80's</label></td>
...
checkboxlist control. My goal is to limit the total number of
selections to be 1 - 5 at most. My problem is that I get a null
reference when I attempt to retrieve an object for an individual list
item, which of course results
in an "object required" error message.
Anyone know what to do? tnx in advance
-Itai.
Here is the code:
<HEAD>
....
<script language="JavaScript">
function ChkMusicTasteSelection(source, arguments) {
var t = 0;
for(var i = 0; i < 31; i++) {
var chkbx = document.all.item("musicTaste_" + i);
// document.write(chkbx) --> null (getElementById() produces the
same effect)
if(chkbx.checked == true){
t++;
}
}
if((t <= 5) && (t >= 1)) {
arguments.IsValid = true;
}
else {
arguments.IsValid = false
}
}
}
</script>
</HEAD>
<body>
<form id="Form1" method="post" runat="server">
...
<TD style="HEIGHT: 188px"><asp:checkboxlist id="musicTaste"
runat="server"
Width="640px" RepeatColumns="5" RepeatDirection="Horizontal">
<asp:ListItem Value="1">60's</asp:ListItem>
<asp:ListItem Value="2">70's</asp:ListItem>
<asp:ListItem Value="3">80's</asp:ListItem>
...
Rendered Output: (browser ie6sp1)
<TD style="HEIGHT: 188px"><table id="musicTaste" border="0"
style="width:640px;">
<tr>
<td><input id="musicTaste_0" type="checkbox" name="musicTaste:0"
/><label for="musicTaste_0">60's</label></td>
<td><input id="musicTaste_1" type="checkbox" name="musicTaste:1"
/><label for="musicTaste_1">70's</label></td>
<td><input id="musicTaste_2" type="checkbox" name="musicTaste:2"
/><label for="musicTaste_2">80's</label></td>
...