Passing A Value To Server

[Jerry Camel]

Basic Web Form... A few text boxes and a checkbox - and a card reader...
The effect I want to accomplish is this:

The basic credit card fields are there and can be filled out. But if the
user swipes the card, I want to fill out the fields automatically and make
them read only. (So far I can do this.)

But I also want a checkbox to appear that indicates the card was swiped.
The user can clear the checkbox, re-enabling the fields so they can be
edited, but then I will no longer consider the data as being swiped. I want
the check box to disappear if they clear it.

Using server controls, if I create a checkbox, but make it not visible, then
it's not available at the client side to work with from client side code.
So I would need to send some flag back to the server to indicate a post back
and have the page re-rendered properly. But how do send info to the server
like that without having a visible control to attach the data to?

(Does this make any sense? Not sure if I'm explaining it well.)

Is there a way to send a value back to the server, in a postback, where the
data is not a property of a server control that's tracking viewstate? The
session object is only available on the server side right?

Any guidance here is appreciated. Thanks.

Jerry

 

[Guest]

to send additional value to server , one commonly used method is

a HiddenControl (you will access it like Request.Forms["HiddenContrlName"]
from code behind)

or a TextBox Webcontrol with size 0 or attribute style='display:none' ..

But if the only purpose of post back is to display/check the checkbox ,
probabaly a better approach is to do the display/check in the client side
javascript ..

Instead of settign Visibility=False, you would just add an attribute to
make it hidden , but still available at client code

CheckBoxName.Attributes.Add("style='display:none'")

 

[Jerry Camel]

Okay... I can have the checkbox on the form and available with 'Display:
None'...

But I can't seem to find the proper syntax to change the display state and
make it visible on the client side...

Thanks.

to send additional value to server , one commonly used method is

a HiddenControl (you will access it like Request.Forms["HiddenContrlName"]
from code behind)

or a TextBox Webcontrol with size 0 or attribute style='display:none' ..

But if the only purpose of post back is to display/check the checkbox ,
probabaly a better approach is to do the display/check in the client side
javascript ..

Instead of settign Visibility=False, you would just add an attribute to
make it hidden , but still available at client code

CheckBoxName.Attributes.Add("style='display:none'")

Basic Web Form... A few text boxes and a checkbox - and a card reader...
The effect I want to accomplish is this:

The basic credit card fields are there and can be filled out. But if the
user swipes the card, I want to fill out the fields automatically and make
them read only. (So far I can do this.)

But I also want a checkbox to appear that indicates the card was swiped.
The user can clear the checkbox, re-enabling the fields so they can be
edited, but then I will no longer consider the data as being swiped. I want
the check box to disappear if they clear it.

Using server controls, if I create a checkbox, but make it not visible, then
it's not available at the client side to work with from client side code.
So I would need to send some flag back to the server to indicate a post back
and have the page re-rendered properly. But how do send info to the server
like that without having a visible control to attach the data to?

(Does this make any sense? Not sure if I'm explaining it well.)

Is there a way to send a value back to the server, in a postback, where the
data is not a property of a server control that's tracking viewstate? The
session object is only available on the server side right?

Any guidance here is appreciated. Thanks.

Jerry

 

[Guest]

Syntax to display ?

document.getElementById("CheckBoxClientName").style.display='' ;
document.getElementById("CheckBoxClientName").Checked = true;

this may help...
http://www.w3schools.com/htmldom/dom_obj_checkbox.asp
http://www.w3schools.com/htmldom/dom_obj_style.asp#layout

Okay... I can have the checkbox on the form and available with 'Display:
None'...

But I can't seem to find the proper syntax to change the display state and
make it visible on the client side...

Thanks.

to send additional value to server , one commonly used method is

a HiddenControl (you will access it like Request.Forms["HiddenContrlName"]
from code behind)

or a TextBox Webcontrol with size 0 or attribute style='display:none' ..

But if the only purpose of post back is to display/check the checkbox ,
probabaly a better approach is to do the display/check in the client side
javascript ..

Instead of settign Visibility=False, you would just add an attribute to
make it hidden , but still available at client code

CheckBoxName.Attributes.Add("style='display:none'")

Basic Web Form... A few text boxes and a checkbox - and a card reader...
The effect I want to accomplish is this:

The basic credit card fields are there and can be filled out. But if the
user swipes the card, I want to fill out the fields automatically and make
them read only. (So far I can do this.)

But I also want a checkbox to appear that indicates the card was swiped.
The user can clear the checkbox, re-enabling the fields so they can be
edited, but then I will no longer consider the data as being swiped. I want
the check box to disappear if they clear it.

Using server controls, if I create a checkbox, but make it not visible, then
it's not available at the client side to work with from client side code.
So I would need to send some flag back to the server to indicate a post back
and have the page re-rendered properly. But how do send info to the server
like that without having a visible control to attach the data to?

(Does this make any sense? Not sure if I'm explaining it well.)

Is there a way to send a value back to the server, in a postback, where the
data is not a property of a server control that's tracking viewstate? The
session object is only available on the server side right?

Any guidance here is appreciated. Thanks.

Jerry

 

[Jerry Camel]

Thanks, but this doesn't seem to have any effect. I tried changing the
style.display property to all kinds of values, but the checkbox never
appears...

Jerry

Syntax to display ?

document.getElementById("CheckBoxClientName").style.display='' ;
document.getElementById("CheckBoxClientName").Checked = true;

this may help...
http://www.w3schools.com/htmldom/dom_obj_checkbox.asp
http://www.w3schools.com/htmldom/dom_obj_style.asp#layout

Okay... I can have the checkbox on the form and available with 'Display:
None'...

But I can't seem to find the proper syntax to change the display state and
make it visible on the client side...

Thanks.

to send additional value to server , one commonly used method is

a HiddenControl (you will access it like Request.Forms["HiddenContrlName"]
from code behind)

or a TextBox Webcontrol with size 0 or attribute style='display:none' ...

But if the only purpose of post back is to display/check the checkbox ,
probabaly a better approach is to do the display/check in the client side
javascript ..

Instead of settign Visibility=False, you would just add an attribute to
make it hidden , but still available at client code

CheckBoxName.Attributes.Add("style='display:none'")



:

Basic Web Form... A few text boxes and a checkbox - and a card reader...
The effect I want to accomplish is this:

The basic credit card fields are there and can be filled out. But

if
the

user swipes the card, I want to fill out the fields automatically

and
make

them read only. (So far I can do this.)

But I also want a checkbox to appear that indicates the card was swiped.
The user can clear the checkbox, re-enabling the fields so they can be
edited, but then I will no longer consider the data as being swiped.

I
want

the check box to disappear if they clear it.

Using server controls, if I create a checkbox, but make it not

visible,
then

it's not available at the client side to work with from client side code.
So I would need to send some flag back to the server to indicate a

post
back

and have the page re-rendered properly. But how do send info to the server
like that without having a visible control to attach the data to?

(Does this make any sense? Not sure if I'm explaining it well.)

Is there a way to send a value back to the server, in a postback,

where
the

data is not a property of a server control that's tracking

viewstate?
The

session object is only available on the server side right?

Any guidance here is appreciated. Thanks.

Jerry

 

[Guest]

Obviously there is some thing not right other than the syntax.. .. Is
there any javascript error when you call the function to display the
checkbox?...

if still no luck, you may want to create a simple HTML page with only
following code in it...

<INPUT TYPE=checkbox ID=chk1 style='display:hidden'>
<INPUT TYPE=button ID=btn1 onClick="toggle()" value="Click to Toggle
Display" >

<script>
function toggle(id)
{
el = document.getElementById("chk1");
var display = el.style.display ? '' : 'none';
el.style.display = display;
}
</script>

Once this works, you can compare with the HTML your aspx generated and that
may help in finding the issue..

This link got a working sample... with code...pls see if this helps..
http://www.sam-i-am.com/work/sandbox/dhtml/setting_style_display.html

Thanks, but this doesn't seem to have any effect. I tried changing the
style.display property to all kinds of values, but the checkbox never
appears...

Jerry

Syntax to display ?

document.getElementById("CheckBoxClientName").style.display='' ;
document.getElementById("CheckBoxClientName").Checked = true;

this may help...
http://www.w3schools.com/htmldom/dom_obj_checkbox.asp
http://www.w3schools.com/htmldom/dom_obj_style.asp#layout

Okay... I can have the checkbox on the form and available with 'Display:
None'...

But I can't seem to find the proper syntax to change the display state and
make it visible on the client side...

Thanks.


to send additional value to server , one commonly used method is

a HiddenControl (you will access it like Request.Forms["HiddenContrlName"]
from code behind)

or a TextBox Webcontrol with size 0 or attribute style='display:none' ...

But if the only purpose of post back is to display/check the checkbox ,
probabaly a better approach is to do the display/check in the client side
javascript ..

Instead of settign Visibility=False, you would just add an attribute to
make it hidden , but still available at client code

CheckBoxName.Attributes.Add("style='display:none'")



:

Basic Web Form... A few text boxes and a checkbox - and a card
reader...
The effect I want to accomplish is this:

The basic credit card fields are there and can be filled out. But if
the
user swipes the card, I want to fill out the fields automatically and
make
them read only. (So far I can do this.)

But I also want a checkbox to appear that indicates the card was swiped.
The user can clear the checkbox, re-enabling the fields so they can be
edited, but then I will no longer consider the data as being swiped. I
want
the check box to disappear if they clear it.

Using server controls, if I create a checkbox, but make it not visible,
then
it's not available at the client side to work with from client side
code.
So I would need to send some flag back to the server to indicate a post
back
and have the page re-rendered properly. But how do send info to the
server
like that without having a visible control to attach the data to?

(Does this make any sense? Not sure if I'm explaining it well.)

Is there a way to send a value back to the server, in a postback, where
the
data is not a property of a server control that's tracking viewstate?
The
session object is only available on the server side right?

Any guidance here is appreciated. Thanks.

Jerry

 

[Jerry Camel]

I'll play with it. Thanks for your help. I was trying to use vbscript, but
I may have to switch to javascript...

Jerry

Obviously there is some thing not right other than the syntax.. .. Is
there any javascript error when you call the function to display the
checkbox?...

if still no luck, you may want to create a simple HTML page with only
following code in it...

<INPUT TYPE=checkbox ID=chk1 style='display:hidden'>
<INPUT TYPE=button ID=btn1 onClick="toggle()" value="Click to Toggle
Display" >

<script>
function toggle(id)
{
el = document.getElementById("chk1");
var display = el.style.display ? '' : 'none';
el.style.display = display;
}
</script>

Once this works, you can compare with the HTML your aspx generated and that
may help in finding the issue..

This link got a working sample... with code...pls see if this helps..
http://www.sam-i-am.com/work/sandbox/dhtml/setting_style_display.html

Thanks, but this doesn't seem to have any effect. I tried changing the
style.display property to all kinds of values, but the checkbox never
appears...

Jerry

Syntax to display ?

document.getElementById("CheckBoxClientName").style.display='' ;
document.getElementById("CheckBoxClientName").Checked = true;

this may help...
http://www.w3schools.com/htmldom/dom_obj_checkbox.asp
http://www.w3schools.com/htmldom/dom_obj_style.asp#layout



:

Okay... I can have the checkbox on the form and available with 'Display:
None'...

But I can't seem to find the proper syntax to change the display

state
and

make it visible on the client side...

Thanks.


to send additional value to server , one commonly used method is

a HiddenControl (you will access it like Request.Forms["HiddenContrlName"]
from code behind)

or a TextBox Webcontrol with size 0 or attribute

style='display:none'
...

But if the only purpose of post back is to display/check the

checkbox
,

probabaly a better approach is to do the display/check in the

client
side

javascript ..

Instead of settign Visibility=False, you would just add an

attribute
to

make it hidden , but still available at client code

CheckBoxName.Attributes.Add("style='display:none'")



:

Basic Web Form... A few text boxes and a checkbox - and a card
reader...
The effect I want to accomplish is this:

The basic credit card fields are there and can be filled out.

But
if

the
user swipes the card, I want to fill out the fields

automatically
and

make
them read only. (So far I can do this.)

But I also want a checkbox to appear that indicates the card was swiped.
The user can clear the checkbox, re-enabling the fields so they

can
be

edited, but then I will no longer consider the data as being

swiped.
I

want
the check box to disappear if they clear it.

Using server controls, if I create a checkbox, but make it not visible,
then
it's not available at the client side to work with from client side
code.
So I would need to send some flag back to the server to indicate

a
post

back
and have the page re-rendered properly. But how do send info to the
server
like that without having a visible control to attach the data to?

(Does this make any sense? Not sure if I'm explaining it well.)

Is there a way to send a value back to the server, in a

postback,
where

the
data is not a property of a server control that's tracking viewstate?
The
session object is only available on the server side right?

Any guidance here is appreciated. Thanks.

Jerry