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Bug with asp.net controlid name

Is there any naming convention or restrictions for a button to be named as "submit"? I have a dropdown list with autopostback= true and a button. It should auto generate textbox with the data from the database
<asp:DropDownList ID="d1" runat="server" DataSourceID="SqlDataSource1" DataTextField="scode" DataValueField="scode" OnSelectedIndexChanged="d1_SelectedIndexChanged" AppendDataBoundItems="true" AutoPostBack="true">
<asp:ListItem Selected="True">0</asp:ListItem>
</asp:DropDownList>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\database.mdf;Integrated Security=True" ProviderName="System.Data.SqlClient" SelectCommand="SELECT [scode] FROM [warehouse]"></asp:SqlDataSource>
<asp:TextBox ID="t1" runat="server"></asp:TextBox>
<asp:Button ID="submit" runat="server" Text="Button" />
codebehind:
protected void d1_SelectedIndexChanged(object sender, EventArgs e)
{
Response.Write("hello");
t1.Text = "abcd";
}
my problem is when i set the controlid of my button as "submit" the postbacks and event handling from the dropdownlist are not triggered but pending. The postbacks and event handling are only triggered when i click on the "submit" button. Pretty sure the problem lies within controlid of the button as I took few hours of trial and error to find a workaround. By renaming the controlid of the button as "submit1" and everything worked perfectly. In short, the textbox are autogenerated with my data whenever I select an item when the controlid of the button is named as submit1". Meanwhile if the controlid of the button is "submit", the data are only generated when i click on the button. This is a small issue as i managed to find the workaround but i would like to know why is this happening.

Using the following minimal code I was able to reproduce your issue on a new web application project with no master page.
<asp:DropDownList runat="server" OnSelectedIndexChanged="d1_SelectedIndexChanged" AutoPostBack="true">
<asp:ListItem>0</asp:ListItem>
<asp:ListItem>1</asp:ListItem>
</asp:DropDownList>
<asp:TextBox ID="ResultLabel" runat="server" />
<asp:Button ID="submit" runat="server" Text="Button" />
Code behind
protected void d1_SelectedIndexChanged(object sender, EventArgs e)
{
ResultLabel.Text = "Postback occurred";
}
If you watch the JavaScript console, you'll see that it results in an error when you change the dropdownlist selection.
Uncaught TypeError: theForm.submit is not a function
This error comes from the bit of code that Web Forms inserts into your page to make postbacks work properly.
That error prevents the postback from completing. The solution is to not have any controls with an ID of submit. You might consider this a bug, but changing the framework to get around this issue would make the framework more complicated than it needs to be.

Is it possible to access element from inside DataList

I am working on a car adverts website. Currently I am trying to do a simple wish list feature allowing the user to store certain cars to his wish list on button click. My cars are presented to the user via DataList. As there is only one button which is repeatedly created on every item from the list I wanted on click to check which record from the DB corresponds to the item where the button was clicked and then add it to another wish list DB.
So far I have come up with this:
<ItemTemplate>
carID:
<asp:Label ID="carIDLabel" runat="server" Visible="false"
Text='<%# Eval("carID") %>' />
<br />
<asp:Button ID="btn_wishList" runat="server" Text="Add to Wishlist"
onclick="btn_wishList_Click" />
<br />
</ItemTemplate>
And the button code:
//table adapters initialization ommited
foreach (DataRow row in carDetailsTable.Rows)
if (carIDLabel.Text == System.Convert.ToString(row["carID"]))
{
//DB insertion ommited
}
The problem I am encountering is that on the button code it says:
The name 'carIDLabel' does not exist in the current context.
Any suggestions how to access the Label's information or any other smarter ways to compare and then add to the wishDB ?

You can put the ID directly in the Button control as a command argument and handle the OnCommand event:
<asp:Button ID="btn_wishList" runat="server" Text="Add to Wishlist" CommandArgument="<%# Eval("carID") %>" OnCommand="btn_wishList_Command" />
Your event handler would be something like:
protected void btn_wishList_Command(object sender, CommandEventArgs e)
{
string id = (string)e.CommandArgument;
}

Bind a textbox value in a label box using c# inside a uframe

I have entered a value in text box and click the button the value should bind in a label.
The code must be in c# not in query. There is no database also.how please say the code behind in c#. It is button click event. while click the button the page should post back and bind the data how to bind a textbox value in a label box using c#. The value must bind in postback method.

easy , take a look at the below code:
<asp:TextBox Id="txt1" runat="server" />
<asp:button Id="btn1" runat="server" onClick="Button1_Click"/>
<asp:Label Id="lbl1" runat="server"/>
//in the code behind implement the Button1_Click
protected void Button1_Click (object sender, EventArgs e)
{
lbl1.Text= txt1.Text;
}

It as easy as the following:
LabelID.Text = TextBoxID.Text;
Where LabelID is the ID of your Label control and TextBoxID is the ID of your TextBox control.
You should place this code inside the button click's event.
Update
Please use for your purpose ASP.NET Web Server Controls.
<asp:TextBox ID="textBoxId" runat="server"/>
<asp:Label ID="labelId" runat="server"/>
Then you can access the values of Text property of both the above controls, like above:
labelId.Text = textBoxId.Text;

Add asp:textbox dynamically in ASP.NET

I have an aspx page made with ASP.NET Web Forms. What i need to create is two asp:textbox fields. I want to be able to dynamically add two new fields below that with the press of a button.
So basically i want to be able to add an infinite amount of "new" textfields. But i'm not sure how to do this in ASP.NET.
Is there perhaps a way to create an arrat of those textfields? So that when a form is posted i can easily iterate over them?
How can i do this?

In your aspx file:
<asp:TextBox runat="server" ID="textbox1"/>
<asp:TextBox runat="server" ID="textbox2"/>
<asp:Button runat="server" ID="btnAdd" OnClick="btnAdd_Click" />
<asp:PlaceHolder runat="server" ID="ph" />
In your aspx.cs file:
protected void btnAdd_Click(object sender, EventArgs e)
{
TextBox tb1 = new TextBox();
TextBox tb2 = new TextBox();
ph.Controls.Add(tb1);
ph.Controls.Add(tb2);
}

You can add this fields and make them hidden(invisible).
And you can show fields on button click (with javascript).
Dynamically adding serverside controls is problem.

AJAX Update Panel - Action button click on drop down selection

Evening all
I have the following scenarion. I have a range of drop down menus where a clietn can select. The code below is wrapped in an update panel but without this, the button click fires a method to retrieve the number of products. So for example, an item is selected from ddlCategory, the btnValidate is clicked and the label returns the number of products within that category.
I have the following code for an update panel - I'm just not sure how to implement if effectively.
<asp:UpdatePanel ID="UpdatePanel1" runat="Server">
<ContentTemplate>
<asp:Label ID="lblSearchResultsStatus" runat="server" Text="Number of results found: "></asp:Label>
<asp:Label ID="lblSearchResults1" runat="server" Text=""></asp:Label>
<br />
<br />
<asp:Button ID="btnValidate" runat="server" Text="Validate Search"
OnClick="btnValidate_Click" Width="120px" />
</ContentTemplate>
</asp:UpdatePanel>
How do I go about wiring the update panel so that when a drop down list item is selected, the buttong is effectively clicked?
Do I have to implement something on each of the ddlSelectedIndexChanged event or is there a property within the update panel that does?
Apologies for the noob question.

The point of the UpdatePanel is to update a portion of the page with an AsyncPostBack instead of reloading the whole page, but in order for the drop-down lists to trigger an AsyncPostBack automatically, they must be on an UpdatePanel. In order to update the labels, they must be on the same UpdatePanel with the labels.
A common pattern to implement what you want to accomplish:
Put the DDLs on the UpdatePanel, and set AutoPostBack="true" on each DDL, so they trigger AsyncPostBacks.
Add an event handler for SelectedIndexChanged on each DDL (can be the same event handler).
Move whatever you do in btnValidate_Click to another method.
Call the new method from btnValidate_Click and the SelectedIndexChanged event handler(s) so they all perform the same function.

You can call your btnValidate_Click event from codebehind at any point, i.e. Page_Load
protected void Page_Load(object sender, EventArgs e)
{
btnValidate_Click(btnValidate, new EventArgs());
}