JavaScript

Re: User control - how to access the element using javascript

19-Jan-12 4:35

I found this function on our default.master

// function onCancel() {
// __doPostBack('RedoPageLoad', '');
// }

and commented this out but still it is still posting back.

AspDotNetDev19-Jan-12 7:39

Thou mewling ill-breeding pignut!

19-Jan-12 7:39

According to this, you can use Request.Form("__EVENTTARGET") to see which control caused the postback.

If that doesn't help, you have a couple options. For one, you could search the HTML source for "doPostBack" to see if there is anything funky that you missed. Also, you can use FireBug or the Chrome debugger to inspect all the JavaScript referenced by the page. If that doesn't get you anywhere, start removing things one by one until the second postback doesn't happen. That will help you narrow down what is causing the problem.

And like I mentioned before, Fiddler2 is a great help for figuring this type of stuff out. It will show you all requests/responses, and all of the data being sent with them to/from the server. And I'm pretty sure you can use some setting to monitor local traffic (that is, web traffic from a Visual Studio web application that is being run locally).

Re: User control - how to access the element using javascript

Member 779716720-Jan-12 12:30

Re: User control - how to access the element using javascript

20-Jan-12 12:30

When I debugged and used the Request.Form("__EVENTTARGET") to see which one is causing the post back then as I thought the dropdown that had the focus is the culprit.

I do not know why or couldn't figure out just because it lost the focus it is doing a post back. As you menioned with your tested example, and I did the same thing and for some reason it is doing a post back which it shouldn't as we tested it.

Member 779716719-Jan-12 9:14

Re: User control - how to access the element using javascript

19-Jan-12 9:14

I kind of figured the issue.

AS I have mentioned I have two User Controls , say UC-A and UC-B. The textBox that is being refreshed is located in UC-A and this is being used by UC-B and UC-B is used by a .aspx page so that is how it is structured.

The UC-B has two DropDownList controls whose AutoPostBack property set to true. And programatically it is a must to set the focus to one of these DropDowlists. So when the page is loaded the DropDownList gets focus and when I try get the focus to the textBox to type in some thing then the DropDowlist is doing a post back as its AutoPostBack property has been set to true.

So I am trying to figure out a way where, if I do not change the of the selectedIndex of the dropdown and just make its focus lost then do not do a post back. I think may be I can try to come up with a javascript function where I can nullify the post back in the javascript function.

Any inputs if this sounds doable?

AspDotNetDev19-Jan-12 10:53

Thou mewling ill-breeding pignut!

19-Jan-12 10:53

So, your theory is that you set focus to the drop down list, then when you click on the textbox the focus is lost on the drop down list and causes a postback? That doesn't make sense to me, as I just created a test page and I couldn't replicate that behavior:

ASP.NET

<%@ Page Language="vb" AutoEventWireup="false" %>

<script runat="server">
  Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    ddlTest.Focus()
  End Sub
</script>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>Test PostBack</title>
</head>
<body>
  <form id="form1" runat="server">
  <div>
    Postback: <%= Page.IsPostBack.ToString() %>
    <br />
    <asp:DropDownList runat="server" ID="ddlTest" AutoPostBack="true">
      <asp:ListItem Text="Item 1" Value="1" />
      <asp:ListItem Text="Item 2" Value="2" />
      <asp:ListItem Text="Item 3" Value="3" />
    </asp:DropDownList>
    <br />
    <asp:TextBox runat="server" />
  </div>
  </form>
</body>
</html>

The focus starts on the drop down list. When I click the textbox, there is no postback. Can you create a test page that replicates the behavior?

Re: User control - how to access the element using javascript

Member 779716720-Jan-12 12:12

Re: User control - how to access the element using javascript

20-Jan-12 12:12

Hi, That is exactly right. It shouldn't postback just because it lost the focus. I too tested it and it doesn't happen in my test page.

I couldn't figure out what the issue is but when I debug our application it loads the page twice. And when the page got loaded I when I click on any where on the page the dropdown looses the focus and it is doing a post back.

It is very annoying to me. I am not sure loading the page twice, which I realized when I debugged the app is somehow may be causing this issue.

I am kind of exhausted with this issues as I couldn't figure what in the world is going on to cause the page load twice.

I really appreciate for replying to all my messages.

If I had any luck I will post it here.

Thanks again.

L

Member 779716719-Jan-12 9:27

Re: User control - how to access the element using javascript

19-Jan-12 9:27

The other way I am thinking is to set the dropwdowns.Focus() some where in one of the the page life cycle events (init, Load, validate, Event, Render, Unload) but not in the same location where it is being set right now? Even then, no matter what by the time it loads the page the dropdownlist would get the focus?

Please provide if this way provides any solution to my issue.

BobJanova18-Jan-12 22:44

BobJanova

18-Jan-12 22:44

Heh, this kind of thing is why I never liked ASP.

Ajax issue

MacRaider416-Jan-12 6:57

16-Jan-12 6:57

Ok I'm trying to learn this and I'm running into a problem and I'm not sure why... I'm going through a tutorial on tizag and I'm getting a error for the onChange event. This is the code:

HTML

<html>
<body>

<script language="javascript" type="text/javascript">
<!-- 
//Browser Support Code
function ajaxFunction(){
	var ajaxRequest;  // The variable that makes Ajax possible!
	
	try{
		// Opera 8.0+, Firefox, Safari
		ajaxRequest = new XMLHttpRequest();
	} catch (e){
		// Internet Explorer Browsers
		try{
			ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (e) {
			try{
				ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e){
				// Something went wrong
				alert("Your browser broke!");
				return false;
			}
		}
	}
	// Create a function that will receive data sent from the server
	ajaxRequest.onreadystatechange = function(){
		if(ajaxRequest.readyState == 4){
			document.myForm.time.value = ajaxRequest.responseText;
		}
	}
	ajaxRequest.open("GET", "serverTime.php", true);
	ajaxRequest.send(null); 
}

//-->
</script>



<form name='myForm'>
Name: <input type='text' onChange="ajaxFunction();" name='username' /> <br />
Time: <input type='text' name='time' />
</form>
</body>
</html>

the error message is "Object expected at JScript - myForm onchange function() (/IntranetSite/order.html:47)
Thanks in advance!!

Not Active16-Jan-12 7:41

Not Active

16-Jan-12 7:41

Have you debugged? Once you have you will be able to find the issue easily.

I would use JQuery and do away with this mess of nested try/catch blocks

No comment

MacRaider416-Jan-12 8:06

16-Jan-12 8:06

yes that is where I got the error message from (the debugger)...
I'm just trying to learn how to get a JavaScript app to work with a database and this was the first part of the tutorial. If you have any better ideas I'm open to them as I haven't invested too much into this one yet Smile | :)

Does onChange="ajaxFunction();" need to be single quote?

AspDotNetDev16-Jan-12 8:20

16-Jan-12 8:20

MacRaider4 wrote:
Does onChange="ajaxFunction();" need to be single quote?

Wouldn't it be faster to test that theory yourself rather than ask if that's the solution and wait for an answer?

EOL

MacRaider416-Jan-12 8:34

16-Jan-12 8:34

I tried it that way and it made no difference, but I was wondering as I would like to learn the "right way"... forgot to mention that in my reply sorry

AspDotNetDev16-Jan-12 8:55

16-Jan-12 8:55

I typically favor using double quotes, though single quotes would work too. When working with ASP.net, I find it easier to sometimes use single quotes, as binding often makes use of double quotes (and having double quotes inside double quotes can cause errors).

EOL

MacRaider416-Jan-12 9:48

16-Jan-12 9:48

Coming from an application background this web stuff is a bit hard to get used to, but doesn't seem too bad all in all. Though it would be nice if you didn't have to go about things in a round about manner.
Back to the original issue, it seems like the function call wants something in the () however I don't have anything specified in the function it self so that doesn't make sense.

MacRaider417-Jan-12 1:59

17-Jan-12 1:59

Ok I've found it... simple mistake I guess...

JavaScript

<script type="text/javascript">

JavaScript

<script type="txt/javascript">

forgot the 'e' in text.... OMG | :OMG:

BobJanova17-Jan-12 3:59

BobJanova

17-Jan-12 3:59

HTML attributes should be enclosed in double quotes, as it's part of the same family as XML. Most browsers will tolerate all sorts of bad markup but to do it right is to use doubles there. Quotes within Javascript can be either, as long as they are paired with the same type, and either is fine in any situation.

MacRaider417-Jan-12 4:12

Rounding a calculation to the nearest 0 or 5

17-Jan-12 4:12

Well if double is the standard then I'll go with double. Thanks for the help!!

DiesenDesign14-Jan-12 15:48

DiesenDesign

14-Jan-12 15:48

I created a PDF form from an excel file. I have everything figured out, except one of the fields in which I am able to round the answer up to the nearest integer, but I need to take it one step further and round it to the nearest 5 or 0. This is what I an using as my custom calculation script:

(Math.ceil(CourseHours/40) + "
");

I have just started learning javascript so I found this off of a website. If anyone could help I would certainly appreciate it. Thank you in advance.

Aniruddha Loya14-Jan-12 20:53

Aniruddha Loya

14-Jan-12 20:53

Use

Math.round( n /5) * 5;

where n is the number you are looking to round off.

Imagination is the one weapon in the war against reality!!!
aniruddhaloya.blogspot.com

DiesenDesign15-Jan-12 14:07

DiesenDesign

15-Jan-12 14:07

That did not work but looking at my email again, the entire script didn't paste. It is

(Math.ceil(CourseHours/40)+"
");

Sorry about that. Thanks much.

modified 15-Jan-12 20:43pm.

Aniruddha Loya15-Jan-12 19:27

Aniruddha Loya

15-Jan-12 19:27

I guess your entire script is not there again...

Anyways... Math.ceil will always take it to next higher number whereas Math.round round it to the nearest integer. So you can choose as per your requirement.

From what I think you are looking to do is - You require (CourseHours/40) rounded to nearest 0 or 5... i.e. the number you eventually looking to round off is the output of - CourseHours/40...
So for my solution to work - 'n' should be substituted by - CourseHours/40
i.e

Math.ceil(CourseHours/40/5) * 5

or use Math.round as per your requirement.

I hope this helps.

Imagination is the one weapon in the war against reality!!!
aniruddhaloya.blogspot.com

DiesenDesign22-Jan-12 11:44

DiesenDesign

22-Jan-12 11:44

It seems to work, but what I am finding is that, as most of the answers will be less than 1, it is rounding it to the nearest 0 or 5 in the thousandths when I need it to be no larger then hundreths. SO all I should have as the final answer is .15 or .35. Does that make sense?