Run a Javascript On Page Load - c#

I would like to know how to run a javascript function on page load.. in my asp.net page. I do not want to do it in from my .cs file OnLoad, I want to keep it in the aspx page if at all possible.
I am new to javascript so any ideas?

<html>
<head>
<script type="text/javascript">
function loadJavaScript()
{
// add code here
}
</script>
</head>
<body onload="loadJavaScript()">
<h1>Java script on load demo</h1>
</body>
</html>
There is a nice example here
or
<script type="text/javascript">
$(document).ready(
function() {
//your code here
});
</script>

Add an onload event to the body html element.
http://www.w3schools.com/jsref/event_body_onload.asp

You can use the HTML body onload event.
or
Use a javascript framework like jQuery and use the $(document).ready() event. .ready()

You can use the RegisterStartupScript to register your javascript snippets from the code behind:
http://msdn.microsoft.com/en-us/library/bb310408.aspx

Related

How to add jquery to asp.net page and format gridview columns

I have seen multiple articles/questions about formatting a gridview rows using jquery.
However consider this my first attempt to write a jquery and use it in an asp.net page.
I manage to do the following, but it doesn't do anything to the gridview. What have I done wrong?
<script src="Scripts/jquery-1.6.1.min.js" type="text/javascript"></script>
</head>
Within body section, after GridView1 is created:
<script language="javascript" type="text/javascript">
$(document).ready(function () {
$("#<%=GridView1.ClientID%> td:nth-child(odd)").css("background-color", "#FFCCCC");
$("#<%=GridView1.ClientID%> td:nth-child(even)").css("background-color", "#99CCFF");
});
</script>
I also have this jquery saved as jqueryColumnColours.js in the scripts folder. So the second question, how can I use .js file without really writing the above function within aspx page?
EDIT:
$(document).ready(function () {
$("#GridView1 td:nth-child(odd)").css("background-color", "#FFCCCC");
$("#GridView1 td:nth-child(even)").css("background-color", "#99CCFF");
});
Include the latest jquery like:
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.8.1/jquery.min.js"></script>
and add the script tag just before closing body section,
</form>
<script type="text/javascript">
$("#grid td:nth-child(odd)").css("background-color", "Tan");
</script>
</body>
I hope it helps!!!
EDIT by bonCodigo:
The only change that works for my page was having http:// instead of //
<script src="http://ajax.microsoft.com/ajax/jquery/jquery-1.4.2.js" type="text/javascript"></script>

All possible ways to trigger a button click in jquery

I want to know all possible ways to trigger a button in jQuery, I tried this but it's not working,
$("#<%=btA.ClientID%>").trigger('click');
Note: its a ASP.Net button and what I want is to trigger button click so that it will trigger a code-behind click method of buttonA.
Try this
$("#<%=btA.ClientID%>").click();
if it doesn't work try to alert this and check if it is getting accessed by JQ
alert($("#<%=btA.ClientID%>").length);
Have you registered the event with jquery in following manner
$(function(){
$("#<%=btA.ClientID%>").click(function(){
// your logic here
});
});
One more thing to confirm, are you loading this button directly on page load or you are having some page update panel which load it afterwords?
If yes then you should bind the event to button in following manner
$(document).on('click',"#<%=btA.ClientID%>", function() {...});
$("#<%=btA.ClientID%>").click();
Or
$("input[id$='yourbuttonId'").click();
Reason that trigger not working is Jquery only allow you to trigger a click that Jquery has created. Use the trigger route after you have written a click listener.
Its beats me since it should be a very straightforward thing. I actually just tried it out and it worked without a hitch. Here is my markup:
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<script src="Scripts/jquery-1.4.1.min.js" type="text/javascript"></script>
<script type="text/javascript">
$(document).ready(function () {
$("#<%=btA.ClientID%>").trigger('click');
});
</script>
<body>
<form id="form1" runat="server">
<div>
<asp:Label ID="lbA" runat="server"></asp:Label>
<asp:Button ID="btA" runat="server" OnClick="btA_Click" Text="Click Me!" />
</div>
</form>
</body>
</html>
... and I have this method in my code behind:
protected void btA_Click(object sender, EventArgs e)
{
lbA.Text = "Hello World!";
}
When the application runs, it triggers the click event of the btA button fires immediately and the Hello World! text is rendered on the label. Check if you could be missing something.
$("#<%=btA.ClientID%>").click();
I believe this is the only other way.
May be you are trying to wire the event,when the control itself is not loaded on to the page.
Try this instead.It buys a little bit of time and then wires up the event.
setTimeout(function () {
$("#<%=btA.ClientID%>").trigger('click');
}, 10);
I always make ClientIdMode="static" so that you can easily call the element with the same id you configured in the page..
So you dont hvae to use ClientID.. More over you cant use asp.net code in a separate js file.
$("#<%=btA.ClientID%>").trigger('click');
to
$("#btA").click();

JQuery don’t work in aspx-page with Masterpage

I have made this example and it works fine on a plain aspx webpage. I use Visual Studio 2010.
Head-part:
<title>Show/hide element</title>
<script type="text/javascript" src="js/jquery.js"></script>
<script type="text/javascript">
$(document).ready(function () {
$('#CheckBoxShowHide').click(function () {
$("#ShowHideElement").slideToggle();
});
});
</script>
<style type="text/css">
#ShowHideElement
{
width:400px;
height:100px;
background-color:Aqua;
}
</style>
Body-part:
<form id="form1" runat="server">
<asp:CheckBox ID="CheckBoxShowHide" runat="server" Text="Show/hide" />
<div id="ShowHideElement">
This is the element for show/hide
</div>
</form>
When I have a masterpage and the same code on the child webpage JQuery dosent work. The loading of the JQuery javascript file fails. The child page and the masterpage are in the same folder. If I put the code on the masterpage it works fine but I want JQuery on the child page too. Please help me.
I can see another problem as well, you are trying to grab the checkbox ID based on its server ID not ClientID. Once a asp control has been rendered onto the client its ID gets changed. Try the following code:
<title>Show/hide element</title>
<script type="text/javascript" src="js/jquery.js"></script>
<script type="text/javascript">
$(document).ready(function () {
$('#<%=CheckBoxShowHide.ClientID%>').click(function () {
$("#ShowHideElement").slideToggle();
});
});
</script>
<style type="text/css">
#ShowHideElement
{
width:400px;
height:100px;
background-color:Aqua;
}
</style>
Body-part:
<form id="form1" runat="server">
<asp:CheckBox ID="CheckBoxShowHide" runat="server" Text="Show/hide" />
<div id="ShowHideElement">
This is the element for show/hide
</div>
</form>
The following line is the only thing I changed:
$('#<%=CheckBoxShowHide.ClientID%>').click(function () {
Hope it helps.
Are you sure your page is loading jQuery, use a absolute URL in your master page to reference the jQuery library.
If jQuery is on your masterpage, it will work on your child page.
Master <head>
<head>
<script type="text/javascript" src="js/jquery.js"></script>
</head>
Child <head>
<head>
<script type="text/javascript">
$(document).ready(function () {
//Do Child jQuery Stuff here....
});
</script>
<head>
If you are having issues the only other thing to check is to make sure that your path to the jquery file is right. (ie Maybe it should be ../js/jquery.js)
Use this to make sure that isn't the issue if the other thing I suggested doesn't work:
For your Master Page <head>:
<head>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
</head>
Or (if you want to host it)
<head>
<script type="text/javascript" src='<%=ResolveURL("~/js/jquery.js")%>'></script>
</head>
Where ~/ is your root.
You should be able to just place the link to the JQuery library in the HEAD section of the master page. When the page is ran it will generate the HTML content for the master page with the link in the HEAD section, the content page should be able to then make user of the JQuery library. I know we had an issue with how the link was being done. Maybe try linking in the HEAD of the master page like this instead:
<script type="text/javascript" src='<% = ResolveURL("~/js/jquery.js") %>' ></script>
The '<% %>' is a way to do inline server side code as the page loads, so the page will inject the correct src given the location of the URL.

Jquery not working inside UserControl

i'm facing a problem tryin to execute a simples jquery inside my userControl. This jquery doesn't has anything with the pages that is goin to load my UC.
the code looks like it:
<script type="text/javascript">
function pageLoad(s, e) {
$(document).ready(function() {
tooltip();
});
}
</script>
i tryied to debug using firebug but not even the breakpoint is reach.. by some reason i think that the browser is just ignoring my script.
it's my first ask here.. sry anything.
you need to write just below lines because ready function get fire automatically when page get loaded with all controls
<script type="text/javascript">
$(document).ready(function() {
tooltip();
});
</script>
how about:
<script type="text/javascript">
$(document).ready(function() {
tooltip();
});
</script>

How to set ASP.NET server time in Javascript

How do you set a textbox value to the equivalent of DateTime.Now in Javascript? I tried these
$('#LastUpdatedTime').val('<%= System.DateTime.Now %>');
$('#LastUpdatedTime').val('<%= System.DateTime.Now.ToString() %>');
Both set the value to the literal string <%= System.DateTime... instead of the time.
Add a javascript function in the aspx which simply returns the server tag, then call this function from your .js file. i.e. in the ASPX add:
function GetTimeNow () { return '<%= System.DateTime.Now.ToString() %>';}
You can't put server tags in a javascript file.
You have to put the code in a file that is handled by the ASP.NET engine, e.g. your .aspx file.
(It's possible to configure the server so that the ASP.NET engine also handles .js files, but that's not a good solution. Javascript files are cached more extensively than regular pages, so it's not certain that the server executes the code each time the file is used.)
Do you have them inside <script> tags on the aspx page?
The aspx page should look something like this
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
</head>
<body>
<form id="form1" runat="server">
<script type="text/javascript">
//put your JAVASCRIPT here
$('#LastUpdatedTime').val('<%= System.DateTime.Now %>');
$('#LastUpdatedTime').val('<%= System.DateTime.Now.ToString() %>');
</script>
</form>
</body>
</html>
That code is fine. The problem is that your <%= System.DateTime.Now %> code is not being parsed as server side code. What's the rest of the page look like?
Edit:
Since it's in an external JS file, you could always rename the ".js" file to ".aspx" so that ASP.Net would start processing it. Then you'd just have to change your <script> tags to use the ".aspx" name instead.
The other option is to configure your server to send ".js" files through the ASP.Net handler.
How about writing out the time on the main .aspx page in the header
<script type="text/javascript">
var now = <%= System.DateTime.Now %>;
</script>
and then doing
$('#LastUpdatedTime').val(now);
You just need to make sure that you name things appropriately so that the JS in the external file gets the value from the global scope.

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