Why erased code (OnClick event) is still running? - html

Question

This little html code (my first html) ask an integer between 1 and 20 and makes a multiplication table. The multiTable is put in an aspx.cs file together. I got a plus task to change mainheader color using javascriptcode (written in script area) by OnCLientClick event. To try whether the coloring javascript function works I temporary deleted OnCLick event connected to Page_Load event. As you can see in the code asp:Button (ID=ButtonCreateMultiplicationTable) hasn't got OnClick event. But it is still functioning. Examin the input and if it is correct makes the table. How it is possible? The Code is not exist. I used: Rebuild Solution, Clean Solution, Restarted VisualStudio, Disabled cache in Chrome Developer Tools. Thank you for any help.
<div id="Date" class="dateTime"><%= (DateTime.Now.Date).ToString("yyyy/MM/dd") + " " + HungarianWeekName((DateTime.Now.DayOfWeek).ToString()).ToString() %> </div>
<div id="mainheader" class="header">
<p class="header1">Szorzótábla </p>
</div>
<div id="InputContainer" class="inputcontainer">
&nbsp
<div id="InputText2" class="inputitem1">Adjon meg egy számot 0 és 21 között </div>
&nbsp
<asp:TextBox class="inputitem2" runat="server" ID="TextBox1"></asp:TextBox>
&nbsp
<asp:Button class="inputitem3" runat="server" Text="Készít" OnClientClick="return ChangeColor()" ID="ButtonCreateMultiplicationTable" />
&nbsp
</div>
<div class="multiplicationtable" id="multitablediv">
<div class="multiplicationcontainer">
<asp:Literal ID="DynamicTable" runat="server"></asp:Literal>
</div>
</div>

Answer 1

An asp:button will always perform a PostBack, whether or not there is an OnClick event.
You either need to return false from the ChangeColor function.
function ChangeColor() {
//rest of your js code
return false;
}
Or don't use an asp:button
<button class="inputitem3" type="button" onclick="ChangeColor()" id="ButtonCreateMultiplicationTable">
Készít
</button>