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I am reading through my vb.net bible, i'm actually trying to learn this stuff.
I have created 1 WebForm, and can't figure out what the problem is. The only error i get is: "Compiler Error Message: BC30451: Name 'BodyID' is not declared."
I have attached my .aspx and .aspx.vb file, so that anyone can look at it. It's such an easy example, and i can do it via the "script language=vb" tag, but i would like to learn both ways.
Thanks in advance.
Part of your problem is the button is not set to RUNAT=server. You need to use the <asp:button> tags in your aspx page.
Also, the BODY tag is not something IIS sees. Everything it uses must have a runat=server tag.
well, why does this work then? I'm just trying to get the scripts out of the main page, like it says in my book. Am i not understanding something?
Code:<%@ Page Language="vb" AutoEventWireup="false" Codebehind="WebForm1.aspx.vb" Inherits="WebApplication2.WebForm1"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<title>ColorChanger</title>
<meta name="GENERATOR" content="Microsoft Visual Studio.NET 7.0">
<meta name="CODE_LANGUAGE" content="Visual Basic 7.0">
<meta name="vs_defaultClientScript" content="JavaScript">
<meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5">
<script language="vb" runat="server">
Sub ChangeButton_click(Source As Object, e As EventArgs)
BodyID.Attributes("text") = TextColor.Value
End Sub
</script>
</HEAD>
<body id="BodyID" runat="server">
<form id="Form1" method="post" runat="server">
<P>Please choose a color:</P>
<SELECT id="TextColor" runat="server">
<OPTION value="#ffffff" selected>White</OPTION>
<option value="#ff0000">Red</option>
<option value="#bfbfbf">Silver</option>
<option value="#ffff10">Yellow</option>
</SELECT>
<P>
<INPUT id="submit1" type="submit" runat="server" value="Change Font Color" onserverclick="Changebutton_click">
</P>
<P> </P>
<DIV>
</DIV>
</form>
</body>
</HTML>
For some reason, and I honestly don't know why, but there are sometimes to use the single file method and other times to use the codebehind. I see what the problem is and I must say that is one of those wierd exception to their whole seperation of code and content idea. It doesn't appear the body or form tags are available in the codebehind, yet are available in single file scripting format. Seems to me, MS should not give one method functionality the other one does not.
I ran into something similar where I needed to write a variable to my page, but was trying to avoid using a server control. I preferred the old style of <p>This my text. here is some example: <%# mytext %>, but my variable on my codebehind was not available. The even stranger thing is there are some codebehind variables and methods that must be used single file style. For example, if you are trying to display a boolean as a checkbox on a datagrid you would type on the aspx file, <%# DataBinder.Eval(Container.DataItem, "myBoolean") %>, but if you had a variable called strWhatThe, it would not see it.
The good thing is you can use single file and codebehind in the same project and it will compile. Maybe MS's intent was to reserve the codebehind for true server side processing and avoiding stuff that Javascript would be better used to accomplish (like changing the textcolor attribute of the body). I know this really doesn't answer why the example works one way and not the other. Sorry. I wish I knew.
ok. i'll make a note that i can't do those generic ones in the outside source.
But can you think of a way (in case i ever have to do this) that if i have a variable coming from one of those, to make it go to the outside source?
When you say "outside source" are you referring to the codebehind? I'm not sure I understand what you are asking.
sorry for my poor wording, i'm still new to this .net stuff. It's a big transition from vb6 to this :)
Yes, i did mean the code behind.
Take my example, of just changing the background color, or the text color; How would i do that with the code-behind? Or would i be forced to put my subroutines in the aspx ?
I tried reproducing the example entirely in codebehind, but I wasn't able to get it work. You can put the script in the aspx file and it should work. Usually the codebehind makes better use of accessing specific controls.
ok. Thanks a load! It seems nobody ever replies to me, either because i'm so ignorant to it, or because my post gets buried.
I really appreciate you taking the time to help me.