Programmatically click asp.net button via javascript?

[Cathryn Johns]

Hi

I have a server-side (asp.net) method that can be called by clicking a
<asp:button> on my webpage. This method should also be called every n
seconds, so I've set up a javascript timer which fires every n seconds.
The problem is that I then don't know how to call the server-side
method.

I figured that since I already have a button calling that method, I
could just emulate the button click, but I've tried two methods and
neither seem to work. document.AllocationsForm.LoadButton.click()
complains that document.AllocationsFrom.LoadButton is null or doesn't
exist, and __doPostBack('LoadButton', '') does a postback but doesn't
actually execute the method.

[Eliyahu Goldin]

In situations like yours I usually introduce a hidden input control for
passing an action code from client to server side. It is much simpler than
trying to mimic exact client-side button click handling.

Eliyahu

"Cathryn Johns" <cj****@gmail.com> wrote in message
news:11**********************@g44g2000cwa.googlegr oups.com...

Hi

I have a server-side (asp.net) method that can be called by clicking a
<asp:button> on my webpage. This method should also be called every n
seconds, so I've set up a javascript timer which fires every n seconds.
The problem is that I then don't know how to call the server-side
method.

I figured that since I already have a button calling that method, I
could just emulate the button click, but I've tried two methods and
neither seem to work. document.AllocationsForm.LoadButton.click()
complains that document.AllocationsFrom.LoadButton is null or doesn't
exist, and __doPostBack('LoadButton', '') does a postback but doesn't
actually execute the method.

[Phillip Williams]

Try:

var btn = document.getElementById(btnName);
if (btn) btn.click();

as I did in this sample:

http://www.societopia.net/Samples/asppage_buttons.aspx
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Cathryn Johns" wrote:

Hi

I have a server-side (asp.net) method that can be called by clicking a
<asp:button> on my webpage. This method should also be called every n
seconds, so I've set up a javascript timer which fires every n seconds.
The problem is that I then don't know how to call the server-side
method.

I figured that since I already have a button calling that method, I
could just emulate the button click, but I've tried two methods and
neither seem to work. document.AllocationsForm.LoadButton.click()
complains that document.AllocationsFrom.LoadButton is null or doesn't
exist, and __doPostBack('LoadButton', '') does a postback but doesn't
actually execute the method.

[intrader]

On Tue, 01 Nov 2005 04:40:41 -0800, Cathryn Johns wrote:

Hi

I have a server-side (asp.net) method that can be called by clicking a
<asp:button> on my webpage. This method should also be called every n
seconds, so I've set up a javascript timer which fires every n seconds.
The problem is that I then don't know how to call the server-side
method.

I figured that since I already have a button calling that method, I
could just emulate the button click, but I've tried two methods and
neither seem to work. document.AllocationsForm.LoadButton.click()
complains that document.AllocationsFrom.LoadButton is null or doesn't
exist, and __doPostBack('LoadButton', '') does a postback but doesn't
actually execute the method.

Candidate for Ajax?

[Cathryn Johns]

Nope, that doesn't work either - if (btn) just returns false. I assume
that this is because in your sample, the button is a regular html
<input type="button"...>, whereas mine is an actual asp.net button
(<asp:button ....>).

Any ideas on how to click an asp.net button?

Phillip Williams wrote:

Try:

var btn = document.getElementById(btnName);
if (btn) btn.click();

as I did in this sample:

http://www.societopia.net/Samples/asppage_buttons.aspx
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Cathryn Johns" wrote:

Hi

I have a server-side (asp.net) method that can be called by clicking a
<asp:button> on my webpage. This method should also be called every n
seconds, so I've set up a javascript timer which fires every n seconds.
The problem is that I then don't know how to call the server-side
method.

I figured that since I already have a button calling that method, I
could just emulate the button click, but I've tried two methods and
neither seem to work. document.AllocationsForm.LoadButton.click()
complains that document.AllocationsFrom.LoadButton is null or doesn't
exist, and __doPostBack('LoadButton', '') does a postback but doesn't
actually execute the method.

[Phillip Williams]

Nope :-)

The buttons in my demo are <asp:button> and they do work. Another demo is
the City of North Vancouver's website (which I developed) where the search
button is also an asp:button and working using btn.Click() too.
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Cathryn Johns" wrote:

Nope, that doesn't work either - if (btn) just returns false. I assume
that this is because in your sample, the button is a regular html
<input type="button"...>, whereas mine is an actual asp.net button
(<asp:button ....>).

Any ideas on how to click an asp.net button?

Phillip Williams wrote:

Try:

var btn = document.getElementById(btnName);
if (btn) btn.click();

as I did in this sample:

http://www.societopia.net/Samples/asppage_buttons.aspx
--
HTH,
Phillip Williams
http://www.societopia.net
http://www.webswapp.com
"Cathryn Johns" wrote:

Hi

I have a server-side (asp.net) method that can be called by clicking a
<asp:button> on my webpage. This method should also be called every n
seconds, so I've set up a javascript timer which fires every n seconds.
The problem is that I then don't know how to call the server-side
method.

I figured that since I already have a button calling that method, I
could just emulate the button click, but I've tried two methods and
neither seem to work. document.AllocationsForm.LoadButton.click()
complains that document.AllocationsFrom.LoadButton is null or doesn't
exist, and __doPostBack('LoadButton', '') does a postback but doesn't
actually execute the method.

[CJ]

Found the problem, and you're right, it had nothing to do with asp.net
buttons :-)

The button is in a .ascx user control which is sitting in a .aspx page,
and I had to prefix the button name with the name of the user control
WebUI element. Once I figured that out, it all worked smoothly.