the asp.net equivalent of the "Request.Form" in asp

i am having problems with a simple web service i am creating in asp.net using C#. does anybody know what Request.Form is in asp.net.
cheers
much appreciatedI've never done classic ASP code, but I think what you're looking for is Request.Params[]

Should still be Request.Form. What is the problem that you are having?

Hi,
Request.Form method was used in classic ASP(3.0)
<form action="hello.aspx" method="post">
Your name: <input type="text" name="fname" size="20">
<input type="submit" value="Submit">
</form>
<%
dim fname
fname=Request.Form("fname")
Response.Write("Hello " & fname)
%>
As in Asp.net forms are posted to itself So Request.Form was not actively used in asp.net.
Iam still now able to understand why you require this in web services.


You can still use Request.Form, but you'll have to make sure the value exists before trying to use it. In Classic ASP, if the value didn't exist it would return an empty string, but in ASP.NET you get Nothing (in VB.NET, which I believe is null in C#).

The best way for OOP

Hi, I'm creating an application with a drop down menu that is populated by a database. The application has 4 other sections which also use the same drop down menu, however each of the 5 sections populate the drop down menu based on the section the user is in.

Currently I am using a single code behind file that queries the db and populates the drop down. I have all 4 sections using the same code behind file. Each section sends the code behind a parameter which allows the method to run the specific section query.

My questions are:

1. Is this the right way to do this?
2. Or should I create a class that all sections use? If I should create a class, what is the code behinds purpose, just to call the class?

I guess I'm kind of confused, it seems as though the code behind really is a class, I can place methods inside it and reuse them whereever I want. I would really like to be sure that I'm following OOP and doing this the correct way.

Thanks, DanBUMP, please help. Any takers? Is this a dumb question?
It's not a dumb question. It's a very good one.

You ask whether it is the "right" way to do it. In terms of OOP, then I'd suggest it's not the right way. The way you've described it, you have to pass in a parameter to your method in order for your code-behind to know how to populate the drop-down list. I'm guessing it's like this (using pseudo-code):

Namespace MyApp
 Public Class Sections
 Public Function GetList( ByVal strSection As String ) As ArrayList
 Dim dstToReturn As New DataSet()
 Select Case strSection
 Case "homepage":
 dstToReturn = SQLquery( "SELECT titles FROM Pages WHERE section='home'" )
 ' for the home page, we also add in a link to the sitemap and search pages
 dstToReturn.Rows.Add( "sitemap" ... )
 dstToReturn.Rows.Add( "seach" ... )
 Case "help page":
 dstToReturn = SQLquery( "SELECT titles FROM Pages WHERE section='help'" )
 ' for this page, we also add in a link to other resources
 dstToReturn.Rows.Add( "forums" ... )
 dstToReturn.Rows.Add( "other resources" ... )
 Case "products page":
 dstToReturn = SQLquery( "SELECT titles FROM Pages WHERE section='products'" )
 Case "order page":
 dstToReturn = SQLquery( "SELECT titles FROM Pages WHERE section='purchase'" )
 End Select
 Return dstToReturn
 End Function
 End Class
End Namespace

If I'm correct, then it is poor OOP design because it requires that you know,in advance, all of the ways in which your function might be used. If you add another section to your site, then you'd have to change your function.

This is bad because it violates thevery fundamental Open Closed Principle. To get an understanding of this and other principles of OOP, start atthis page. Follow its links andsearch for any terms you don't understand.

There are many principles and ideas about OOP, so I wouldn't recommend getting too concerned about finding the "right way". Get the gist of the Open Closed Principle, and then just start coding. You'll soon stub your toe in places where you find you should have done something differently, and you'll remember next time.

As a kind of litmus test though ... if you're using If/Then or Select Case statements, then you're probably not creating clean OOP code. Such loops are poor for performance and mean you are looking for thingsknown in advance.

Is that any help?
Dan, what you're doing is ok providing all sections are in the same page. if not then a seperate class may be useful. Also are you using a stored proc to return the data or dynamic sql in the code? if your rdbms supports sprocs then i would use one to improve performance (and to make maintenance easier).

To clear up your confusion, the code behind file IS a class. It inherits from the page class. Your aspx file in turn also compiles to a class that inherits from your code behind class. Cool hey!

Jon.

The difference between creating an instance of an object

Could someone tell me in plain english was is the difference between

Dim MyObject As SomeType

and

Dim MyObject As New SomeType

and

Dim MyObject = New SomeType

Dim MyObject as SomeType = Creating a variable that holds an object of SomeType.

Dim MyObject as New SomeType = Creating and instantiating an object of SomeType.

Dim MyObject = New SomeType = Invalid syntax in vb.net. You need to specify the default type as variant is no longer supported in ASP.NET.
Ok, now I understand.

So if I have something like Fruit.Apple and Value is part of this as in Fruit.Apple.Value, I can do this...

Dim Food As Fruit.Apple
Food.Value

It looks like a way of shortening the name of an object.

Now, I have another question. How do you know when is the appropriate time to create and instantiate a new object rather than just use the above method?

Sorry if my question seems too easy, but I didn't do much of this stuff in regular ASP.
Well yes and no.

Lets think of this another way. Lets take your Fruit object. Your fruit has properties - color, weight, type, etc. You would create a class that describes this like so:

Public Class Fruit
 Private _type As String
 Private _color As String
 Private _weight As Decimal
 Public Property Type() As String
 Get
 Return _type
 End Get
 Set(ByVal Value As String)
 _type = Value
 End Set
 End Property
 ' Add other properties for color and weight also
End Class

Then in your code you would instantiate a new Fruit object like:

Dim objFruit as New Fruit
'Then set properties of the fruit
With objFruit
 .Type = "Apple"
 .Color = "Red"
 .Weight = 2.2
End With

It is appropriate to create a class whenever you are going to possibly reference the object from multiple places in your code.

Greg