Enabling Disabling button asp .net - using javascript
Currently in my application I am having a button and a text box. The user types something in the textbox and then presses the button. What I want is that:
The search button should should stay disabled when the page loads for th开发者_StackOverflow社区e first time. I can achieve that by setting it to disabled in the code behind file.
Now I want it to remain disabled when the user types upto 2 characters. The moment the user types third character the button should get enabled automatically.
The important thing is that it has to be done without asp .net AJAX since this website will be run from old mobile phones. So only pretty basic javascript or jquery is supported.
Any help will be appreciated.
Thanks
Varun
in order to use the document.getElementById in asp.net and not have to use the full name, you should let asp.net provide it. Instead of:
document.getElementById("ctl00_ctl00_phContent_phPageContent_btnSearch")
Try:
document.getElementById('<%= btnName.ClientID %>')
Where btnName
is the asp:Button
Id
. The <%=
code will generate the actual button id, fully qualified, so you don't have to worry about things changing with the hard coded id.
I got this to work with a HTML text box, I don't think you can do it with a asp.net text box:
<head>
<script type="text/javascript">
function TextChange() {
var t = document.getElementById("Text1");
var b = document.getElementById("Button1");
if (t.value.length > 2) {
b.disabled = false;
}
else {
b.disabled = true;
}
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<input id="Text1" type="text" onkeyup="TextChange();" />
<asp:Button ID="Button1" runat="server" Text="Button" Enabled="False" />
</div>
</form>
</body>
If you're using jQuery, use
$(<selector>).val().length
to get the size, then you can set the button's disabled attribute with
$(<button selector>).attr('disabled',false).
精彩评论