Web Development

Passing Variables Between Pages in ASP.NET

28-Jan-02 10:04

omkamal wrote:
Well, I have immense hope in .NET and Web services. I think it will start a great revolution in web community.

I doubt it will be anything that can be classified as revolution. But I am sure that more and more of .NET will be around and people who knows anything about it will be needed. Beside that it is a cool thing to learn. So we shall see what will come out of it...

21-Jan-02 21:48

Hi,

I've just getting into ASP.NET and am wondering what is the best practice on passing variables between pages. I have done a lot of programming in classic ASP and used querystrings a lot to pass information between 2 pages.

Given that one of ASP.NET's advantages is strongly typed variables it seems a bit nasty to have to resort to using querystrings and then converting values into which ever type is expected e.g.:

string strMode = Request.QueryString["mode"];

if( strMode == "add")
{
if(Request.QueryString["myid"] != null)
{
short nMyID = Convert.ToInt16(Request.QueryString["myid"]);
DetailsFromAddPage(nMyID);
}
}

None of the books I have seen really mention this so i'm thinking that i've missed something!

If someone could give me a pointer in the right direction I would be grateful

Thanks.

Re: Passing Variables Between Pages in ASP.NET

Konstantin Vasserman23-Jan-02 15:08

.NET Positioning controls programatically

23-Jan-02 15:08

I don't think there is another way short of storing values in Session variables, database or text file. Dead | X|

Now if you can use Server.Transfer() instead of Response.Redirect() you won't even need to pass anything because the page you call will be executed in the same process and I believe that all the variables from the first page will be accessible in the second page.

Eivind21-Jan-02 4:15

Eivind

21-Jan-02 4:15

I need to attach different (self-created) user controls to my web form at run-time, and I want to specify their position when/after they are loaded.

The only way I have managed to do this so far, is by drawing a control container (like the Placeholder control) at designtime, but I need to do it all at runtime.

Does anyone know how to do this?

Thanks! Confused | :confused:

Eivind

Konstantin Vasserman21-Jan-02 5:04

21-Jan-02 5:04

Try something like this:

Label lblNew = new Label();
lblNew.Text = "This is a new label";
lblNew.Style["position"] = "absolute";
lblNew.Style["top"] = Convert.ToString(150);
lblNew.Style["left"] = Convert.ToString(200);
Controls.Add(lblNew);

Eivind21-Jan-02 11:39

Eivind

21-Jan-02 11:39

Thanks, but this metod has a minor drawback:

It doesn't work for controls that needs to be inside a Form tag (i.e. the TextBox Control).

The reason for this, I guess, is that .NET output the control after the tag in the web-page, which I believe is not ideal.

I guess that I somehow should try to get a reference to the Page's Form, but I don't know how... (yes, I'm a newbie!)

Eivind

Konstantin Vasserman21-Jan-02 11:46

21-Jan-02 11:46

Well, if your form has an id you should be able to refer to it using that id. For example:

...

<form id="frmMain" ....>

...

frmMain.Controls.Add(myLabel);

...

Another solution might be is to just place all the controls in the form from the very beginning, but hide the ones you don't need and show them when necessary.

Eivind21-Jan-02 12:33

Eivind

21-Jan-02 12:33

Thank you Konstantin, this was what I needed to get things right!

By using the FindControl() method, I got a reference to the Form. Here's the code for anyone interested.

Control myUserControl;
myUserControl = Page.LoadControl("Login.ascx"); //my custom user control
Control activeForm;
activeForm = Page.FindControl("myFormId"); //the id of my - element
activeForm.Controls.Add(myUserControl); //add the user control to the form

Big Grin | :-D

form validation

Bruno Lemos21-Jan-02 3:21

21-Jan-02 3:21

Hi how can i validate some form fields without using asp:RequiredFieldValidator or asp:RegularExpressionValidator?
I have this:

asp label tag id="lNome" text="Name:" runat="server" />	asp textbox tag id="tNome" size="30" runat="SERVER" />

and the function:

Sub Validate()

if tNome.value = "" then '??? doesnt work!!!
msgbox ("Please Insert a string")
else
msgbox ("OK") ' How Can I submit the form here??
end if

End Sub

Can someonelse help me please???
Thanx in advance
bRunO

Konstantin Vasserman21-Jan-02 4:43

21-Jan-02 4:43

1. What is tNome? I don't see it anywhere on your form...

2. If your script is to run at server, where do you expect your Msgbox to popup?

3. Look into creating of Custom Validators if default ones do not do what you need:

http://www.gotdotnet.com/quickstart/aspplus/doc/webvalidation.aspx#custom

Bruno Lemos21-Jan-02 5:08

21-Jan-02 5:08

I've corrected the post... there is a problem when i write asp:label ...
By the way how can i submit a form in a VBS function?? Frown | :(

Konstantin Vasserman21-Jan-02 5:29

21-Jan-02 5:29

Bruno Lemos wrote:
I've corrected the post... there is a problem when i write asp:label

OK. System.Web.UI.WebControls.TextBox asp control does not have a Value property. You have to do tNome.Text on the server side.

Bruno Lemos wrote:
By the way how can i submit a form in a VBS function?

Do you mean how to run a client-side function on submit? This is why you should use Custom Validator - it will take care of it for you - you will be able to specify client-side and server-side validation functions. It is very simple, just look at the link I gave you.

Bruno Lemos21-Jan-02 5:51

21-Jan-02 5:51

ok thanx for your help. is it possible this?

validate a field, if its not valid, appears a red label "Incorrect Entry"
if its valid submits the form to another page (page2.aspx)?

thanx again

Konstantin Vasserman21-Jan-02 6:01

21-Jan-02 6:01

You don't submit the form to the other page per say, instead you validate everything in this page and then redirect user to the other page. For example, in your Page_Load or myButton_Click event handler functions on the server side you can do this:

If Page.IsValid Then
   Response.Redirect("page2.aspx")
End If

Bruno Lemos21-Jan-02 6:04

21-Jan-02 6:04

ok..
sorry being so newbie
one more question please:

when i redirect to page2.aspx is it possible to get the value of the field with Request.Form["tName"] in order to insert it in a Db?

Konstantin Vasserman21-Jan-02 6:13

21-Jan-02 6:13

Not if you redirect. You could store it into a Session variable, but it is probably better to do a Server.Transfer("page2.aspx") instead of Redirect than. If you do the transfer you will be able to do Request.Form("...") in the other page.

Bruno Lemos21-Jan-02 6:20

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21-Jan-02 6:20

ok thanx for all your help... i'll try some stuff with your tips and if i have more questions i'll post them ok? thanx again Big Grin | :-D

20-Jan-02 19:23

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What happened to the HTML/CSS Article section?

Paul Watson19-Jan-02 7:52

Paul Watson

19-Jan-02 7:52

What happened to the HTML/CSS Article section? I cannot find it in the left hand bar on the home page. The folders still exist (I checked my first article and it was still there.)

Am I just missing it? Also ASP is not there, though I guess ASP is being put into the .NET section.

Still, what happened to the HTML/CSS Article section?

regards,
Paul Watson
Bluegrass
Cape Town, South Africa

"The greatest thing you will ever learn is to love, and be loved in return" - Moulin Rouge

Martin Marvinski wrote:
Unfortunatly Deep Throat isn't my cup of tea

Do you Sonork? I do! 100.9903 Stormfront

Re: What happened to the HTML/CSS Article section?

Konstantin Vasserman19-Jan-02 12:37

Re: What happened to the HTML/CSS Article section?

19-Jan-02 12:37

Everything is sill there as far as I can see. I think you need to select All Topics tab to see it.

What I want to know is what happened to article submission wizard. It says it is temporary unavailable. I have an article to submit and now I am not sure if I should just email it to Chris or wait for wizard to come back. The thing is that I don't know if it is down for a long time now or is it just today or what...

Paul Watson20-Jan-02 1:17

Paul Watson

20-Jan-02 1:17

Konstantin Vasserman wrote:
I think you need to select All Topics tab to see it.

Aahhhh Smile | :)

Thanks Konstantin.

Konstantin Vasserman wrote:
What I want to know is what happened to article submission wizard

Me too, was about to submit a second article and found the wizard down. I assume Chris is improving it no end Big Grin | :-D

So the wait, not sure how long, should be worth it.

regards,
Paul Watson
Bluegrass
Cape Town, South Africa

"The greatest thing you will ever learn is to love, and be loved in return" - Moulin Rouge

Martin Marvinski wrote:
Unfortunatly Deep Throat isn't my cup of tea

Do you Sonork? I do! 100.9903 Stormfront

Re: What happened to the HTML/CSS Article section?

Konstantin Vasserman20-Jan-02 4:54

jumping to a different page

20-Jan-02 4:54

Paul Watson wrote:
Me too, was about to submit a second article and found the wizard down. I assume Chris is improving it no end So the wait, not sure how long, should be worth it.

Well, according to Chris there is a problem with it that they are trying to fix and they hope to get it working soon. So we'll just wait. Maybe I should write another article while waiting - I still have 20 more to go to get my platinum membership status... Smile | :)

omkamal17-Jan-02 10:29

omkamal

17-Jan-02 10:29

Hai,

Its surprising me, that no one discusses about the traditional . It didnt work. Because the submit button always tries to call the Page_Load function of the same page.

Surprising enough, none of Microsoft's documentation discusses about the action attribute. Wondering whether it is not required since the form itself is running on the server.

Then how would I jump to a different page?

omkamal

Re: jumping to a different page

Konstantin Vasserman17-Jan-02 11:20