I Have an aspx page that contains 2 buttons “Update” and “Default”. I have a dropdown list which contains a few values, say 1 to 10. When I click on Default button, the dropdown is set to a default value, say 4. If I wish to set the dropdown value to 3, I choose 3 and click on Update button and the changes are saved somewhere, maybe a DB.
Initially, Update button is disabled. Only if any changes are made to the dropdown, the Update button is enabled. Assuming that the Update button is initially disabled, I click the Default button to set the dropdown to its initial value. When I do that, a postback happens during which the Update button suddenly becomes enabled and then disabled. How do I avoid this? During page refresh, I don’t want the disabled Update button to become enabled and then disabled. ALl this happens in a millisecond but its still visible.
is there any way out of this?
Design code is as follows:
ASPX
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="LogSettings.aspx.cs" Inherits="Settings_LogSettings" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>Diagnostic Server Configuration Tool</title>
<link rel="stylesheet" type="text/css" href="../css/style001.css" />
<style type="text/css">
a.info
{
position: relative; /*this is the key*/
z-index: 24; /*background-color:#ccc;*/
color: #000;
border-width: 0px;
border-style: none;
text-decoration: none;
}
a.info:hover
{
z-index: 25;
background-color: #ff0;
}
a.info span
{
display: none;
}
a.info:hover span
{
/*the span will display just on :hover state*/
display: block;
position: absolute;
bottom: 2em;
right: 2em;
width: 15em;
border: 1px solid #0cf;
background-color: #cff;
color: #000;
text-align: left;
padding: 5px;
}
</style>
<script language="javascript" type="text/javascript">
function setDefaults() {
if (document.getElementById("dlLoggingLevel").value != document.getElementById("dlLoggingLevel_Def").value) {
document.getElementById("dlLoggingLevel").value = document.getElementById("dlLoggingLevel_Def").value;
document.getElementById("imgLoggingLevel").src = "../images/field_ok.png";
document.getElementById("imgLoggingLevelUndo").style.display = "inline";
document.getElementById("btnUpdate").disabled = false;
}
if (document.getElementById("txtMaxFileSize").value != document.getElementById("txtMaxFileSize_Def").value) {
document.getElementById("txtMaxFileSize").value = document.getElementById("txtMaxFileSize_Def").value;
document.getElementById("imgMaxSize").src = "../images/field_ok.png";
document.getElementById("imgMaxSizeUndo").style.display = "inline";
document.getElementById("btnUpdate").disabled = false;
}
}
function isNumberKey(evt) {
var charCode = (evt.which) ? evt.which : event.keyCode
if (charCode > 31 && (charCode < 48 || charCode > 57))
return false;
return true;
}
</script>
<script language="javascript" type="text/javascript" src="../Css/wcf_validate.js"></script>
</head>
<body>
<form id="form1" runat="server">
<div>
<br />
<div class="divEditHeader" id="EditHeader">
<h1>
Logging Configuration
</h1>
<table width="100%">
<tr>
<td align="left">
<asp:Button CssClass="formEditBtn" runat="server" ID="btnUpdate" Text="Update" OnClick="btnUpdate_Click"
Enabled="false" />
<button class="formEditBtn" onclick="javascript:setDefaults();" causesvalidation="false">
Default</button>
</td>
<td align="right">
</td>
</tr>
</table>
</div>
<br />
<table class="InputTable">
<tr class="Prompt">
<td class="Prompt">
Logging Level
</td>
<td>
<asp:DropDownList runat="server" ID="dlLoggingLevel">
<asp:ListItem Text="NONE" Value="none"></asp:ListItem>
<asp:ListItem Text="FATAL" Value="fatal"></asp:ListItem>
<asp:ListItem Text="ERROR" Value="error"></asp:ListItem>
<asp:ListItem Text="WARNING" Value="warning"></asp:ListItem>
<asp:ListItem Text="INFO" Value="info"></asp:ListItem>
<asp:ListItem Text="DEBUGLOW" Value="debuglow"></asp:ListItem>
<asp:ListItem Text="DEBUGMEDIUM" Value="debugmedium"></asp:ListItem>
<asp:ListItem Text="DEBUGHIGH" Value="debughigh"></asp:ListItem>
<asp:ListItem Text="DEBUGALL" Value="debugall"></asp:ListItem>
</asp:DropDownList>
<img id="imgLoggingLevel" src="../images/blank.png" />
<asp:TextBox runat="server" ID="dlLoggingLevel_Init" Style="display: none"></asp:TextBox>
<asp:TextBox runat="server" ID="dlLoggingLevel_Def" Style="display: none"></asp:TextBox>
<img id="imgLoggingLevelUndo" src="../images/restore.png" style="display: none; cursor: hand"
onmouseover="this.src='../Images/restore_hov.png'" onmouseout="this.src='../Images/restore.png'"
onclick="restoreValue('dlLoggingLevel','dlLoggingLevel_Init','imgLoggingLevel','imgLoggingLevelUndo')" />
</td>
<td>
<a href="javascript: void 0" class="info">
<img src="../images/help.png" border="0">
<span><font size="2">Enter the desired level of diagnostic data logging. Default: INFO.
</font></span></a>
</td>
</tr>
<tr class="Prompt">
<td class="Prompt">
Maximum Log File Size(MB)
</td>
<td>
<asp:TextBox runat="server" ID="txtMaxFileSize" Width="36px" MaxLength="3"></asp:TextBox>
<asp:TextBox runat="server" ID="txtMaxFileSize_Init" Style="display: none"></asp:TextBox>
<asp:TextBox runat="server" ID="txtMaxFileSize_Def" Style="display: none"></asp:TextBox>
<img id="imgMaxSize" src="../images/blank.png" />
<asp:CustomValidator runat="server" ID="valMaxSize" ControlToValidate="txtMaxFileSize"
Display="Dynamic" ErrorMessage="" ClientValidationFunction="MaxSize_Validate"></asp:CustomValidator>
<img id="imgMaxSizeUndo" src="../images/restore.png" style="display: none; cursor: hand"
onmouseover="this.src='../images/restore_hov.png'" onmouseout="this.src='../images/restore.png'"
onclick="restoreValue('txtMaxFileSize','txtMaxFileSize_Init','imgMaxSize','imgMaxSizeUndo')" />
</td>
<td>
<a href="javascript: void 0" class="info">
<img src="../images/help.png" border="0">
<span><font size="2">Enter the maximum log file size in MB. Default: 2 MB. Range: 1
- 100 MB. </font></span></a>
</td>
</tr>
</table>
<br />
<asp:Label runat="server" ID="lblMessage" Font-Bold="true"></asp:Label>
<br />
</div>
</form>
</body>
</html>
Code-Behind
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using DiagnosticCommon;
using System.Drawing;
public partial class Settings_LogSettings : System.Web.UI.Page
{
const string EnvVariable = "DIAGNOSTICSERVER";
const string ConfigFileName = "DiagnosticService.exe.config";
protected void Page_Load(object sender, EventArgs e)
{
if (Security.EnforceSecurity())
Response.Redirect("Login.aspx");
if (!IsPostBack)
{
DebugHelper.MaxDebugLevel = DebugHelper.Parse(ConfigReader.GetValue("LoggingLevel"));
DebugHelper.MaxLogFileSize = long.Parse(ConfigReader.GetValue("LogFileSize"));
txtMaxFileSize.Attributes.Add("onchange", "javascript:MaxSize_Validate('',this);");
txtMaxFileSize.Attributes.Add("onkeypress", "return isNumberKey(event)");
dlLoggingLevel.Attributes.Add("onchange", "javascript:Logging_Validate('',this);");
BindData();
BindInitData();
BindDefaults();
}
}
private void BindData()
{
string installPath = Environment.GetEnvironmentVariable(EnvVariable);
try
{
dlLoggingLevel.SelectedValue = ConfigReader.GetValue("LoggingLevel");
txtMaxFileSize.Text = ConfigReader.GetValue("LogFileSize");
}
catch (Exception ex)
{
lblMessage.Text += ex.Message + "<br>" + installPath;
lblMessage.ForeColor = Color.Red;
}
}
private void BindInitData()
{
string installPath = Environment.GetEnvironmentVariable(EnvVariable);
try
{
dlLoggingLevel_Init.Text = ConfigReader.GetValue("LoggingLevel");
txtMaxFileSize_Init.Text = ConfigReader.GetValue("LogFileSize");
}
catch (Exception ex)
{
lblMessage.Text += ex.Message + "<br>" + installPath;
lblMessage.ForeColor = Color.Red;
}
}
protected void btnCancel_Click(object sender, EventArgs e)
{
}
protected void btnSubmit_Click(object sender, EventArgs e)
{
}
protected void btnUpdate_Click(object sender, EventArgs e)
{
try
{
lblMessage.Text = "";
ConfigReader.SetValue("LoggingLevel", dlLoggingLevel.SelectedValue);
ConfigReader.SetValue("LogFileSize", txtMaxFileSize.Text);
lblMessage.Text = "Configuration updated.";
lblMessage.ForeColor = Color.Green;
btnUpdate.Enabled = false;
BindInitData();
}
catch (Exception ex)
{
lblMessage.Text += ex.Message;
lblMessage.ForeColor = Color.Red;
}
}
private void BindDefaults()
{
try
{
dlLoggingLevel_Def.Text = ConfigReader.GetDefault("LoggingLevel");
txtMaxFileSize_Def.Text = ConfigReader.GetDefault("LogFileSize");
}
catch (Exception ex)
{
lblMessage.Text = ex.Message;
lblMessage.ForeColor = Color.Red;
btnUpdate.Enabled = false;
}
}
}
Since the button has no
typedefined, the default type is used which is a submit button.This means that when you click the
Defaultbutton, the JS code is running but then the form is submitted.To avoid the submission simply make the button be ordinary button: