473,703 Members | 3,140 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

Client-Side Validation and Double-Click Problem

I have written an ASP.Net application that uses the standard
client-side and server-side validation for various fields on the form.
Some of the customers that use the form report symptoms that appear to
be the result of double-clicking the submit button on the form.

The form has three ASP:Button tags, each of which gets translated into
INPUT TYPE="SUBMIT" HTML elements. One submits the form's data. One
logs the user out. And the other clears the form.

I tried to disable the Submit button in the form's onsubmit event, but
that event is used by the client-side validation. Also, I found that it
was difficult to detect which button was clicked on the form. Finally,
disabling the Submit button made the server process ignore the
btnSubmit_Click event. This technique worked with ASP applications, but
doesn't work with ASP.Net applications.

I had to implement a different solution to solve these problems.

1. First, I added attributes to each button on the form in the
Page_Load event. I implemented a handler for the "onmousedow n" event,
not the "onclick" event. It didn't seem to work with the onclick event.
btnSubmit.Attri butes("onmoused *own") = "fIsSubmit=true ;"
btnLogout.Attri butes("onmoused *own") = "fIsSubmit=fals e;"
btnClear.Attrib utes("onmousedo *wn") = "fIsSubmit=fals e;"

2. Then, I added Javascript to the HTML portion of the page as follows.
I had to override the default client-side onsubmit event handler.
Standard validation still works when tabbing from field to field.

var fSubmit = false; // This flag is the debounce flag
var fIsSubmit = false; // This flag gets set or cleared by the
onmousedown events
function Init()
document.Form1. txtVoucher.focu *s();
// Override the default submit routine that ASP.Net uses.
document.Form1. onsubmit = OnSubmit;

// This routine does client-side validation.

function OnSubmit() {
// Was it the submit button?
if ( fIsSubmit )
// Added client-side validation to debounce the button, btnSubmit
// Call the same client validation method to validate the number
var args = new Object();
args.Value = document.Form1. txtAmount.value *;
args.IsValid = false;
ValidateAmount( document.Form1, args);

// Make sure the other form values are ok too
if ( TrimString(docu ment.Form1.txtV *oucher.value) != '' &&
TrimString(docu ment.Form1.txtH *ackLicense.val ue) != '' &&
TrimString(docu ment.Form1.txtA *mount.value) != '' &&
args.IsValid )
// debouce the click (disabling the button doesn't work).
if ( !fSubmit ) {
fSubmit = true; //document.Form1. btnSubmit.dis*a bled =
return true;
return false;
return true;
function TrimString(theV alue)
// Trim logic removed for brevity
// This is the same function that the client-side validation uses
// for the numeric fields in the form.

function ValidateAmount( source, args)
var sValue = TrimString(args .Value).toStrin *g();
sValue = sValue.replace(/[\$,]/g, '');
if (isNaN(sValue))
args.IsValid = false;
var dValue = parseFloat(sVal ue);
if ( dValue < 1 || dValue > 500 )
args.IsValid = false;
args.IsValid = true;
// -->

Not as easy as I thought it would be. The real question is, why does
the double-click cause the form to submit twice, but only on some

Nov 19 '05 #1
1 5236
> I tried to disable the Submit button in the form's onsubmit event

Not sure if this helps, but what I have done in the pass is instead of
disabling it, just hiding it.

So, I'd have something like this (pseudo code for the javascript):

<div><button onclick="set this div to display:none, set the other one to
display: block"></div>
<div display: none>Updating database...</div>
Nov 19 '05 #2

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

by: ian maclure | last post by:
I'm writing a client-server app. Client controls Server which in turn configures and controls a bunch of hardware. I want to be able to start the server from my client. Now in C/C++ one could simply run the appropriate command string through a standard "system()" call which is relatively simple. JAVA on the other hand seems to require something like RMI to do it.
by: Raquel | last post by:
How do I know whether the 'runtime client' and the 'application development client' are installed on my machine? When I issue the command "db2licm -l", it gives the following output: Product Name = "DB2 Personal Edition" Product Password = "DB2PE" Version Information = "8.1" Expiry Date = "Permanent" Annotation = "" Other information = ""
by: Tim Northrup | last post by:
Help! We have DB2 V7.2 (fixpak 12) installed on Windows2003 Server, and the latest V7.2 client installed on another system. The DB2CODEPAGE on all systems is set to 1208, and the database was created with code set UTF-8 / codepage 1208. (Note: Running our test application described below on the database host as opposed to a separate client system produced the same results as described below). When we perform an INSERT statement...
by: Rhino | last post by:
I am trying to verify that I correctly understand something I saw in the DB2 Information Center. I am running DB2 Personal Edition V8.2.1 on Windows. I came across the following in the Info Center: To return a result set from a procedure to the originating application, use the WITH RETURN TO CLIENT clause. When WITH RETURN TO CLIENT is specified on a result set, no nested procedures can access the result set.
by: Ankit Aneja | last post by:
i am doing here some some socket-client work in C# windows service it is working fine for multiple clients now i want to limit these multiple clients to 25 for example i want that when service starts objects for all these 25 clients are created and when client connects it should be accepted and will not allow more than 25 clients to connect and when client diconnects that object can be allocated to another client who requests i am not...
by: Sandeep Singh | last post by:
I am making socket client application in C# how can i get ip address of client who has connected to server
by: Ankit Aneja | last post by:
The code of classes given below is for server to which clients connect i want to get ip address of client which has connected pls help how can i get //listen class public class listen {
by: khu84 | last post by:
Here is client server very simple code, seems to work with telnet but with with web client code gives blank output. Following is the server code:- <?php function createSocketServer($host='',$port=2222) { $max_clients = 10;
by: nsaffary | last post by:
hi I hava a client/server program that run correctly when i run it in one computer(local) but when I run client on a one computer and run server run on another, connection does not stablish.(I set server machine IP for client and server) please guide me? server : #include <winsock2.h> #include <iostream> #include <stdio.h> #include <string.h> #include <windows.h> #pragma comment(lib, "ws2_32");
by: MMcCarthy | last post by:
http://bytes.com/images/howtos/projectscope_blocks.jpgAs a freelance IT consultant for over 10 years, Iíve come to appreciate well defined project scopes. A project scope is a common understanding between you and your client as to what work is included in, or excluded from, a project.In a study done by CA towards end of last year, one third of all projects end up over budget and over-spend typically 10-20% of the original budget. Primary reasons...
by: marktang | last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, weíll explore What is ONU, What Is Router, ONU & Routerís main usage, and What is the difference between ONU and Router. Letís take a closer look ! Part I. Meaning of...
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it. First, let's disable language synchronization. With a Microsoft account, language settings sync across devices. To prevent any complications,...
by: Oralloy | last post by:
Hello folks, I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>". The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed. This is as boiled down as I can make it. Here is my compilation command: g++-12 -std=c++20 -Wnarrowing bit_field.cpp Here is the code in...
by: Hystou | last post by:
Overview: Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
by: isladogs | last post by:
The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM). In this session, we are pleased to welcome a new presenter, Adolph Duprť who will be discussing some powerful techniques for using class modules. He will explain when you may want to use classes instead of User Defined Types (UDT). For example, to manage the data in unbound forms. Adolph will...
by: conductexam | last post by:
I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and then checking html paragraph one by one. At the time of converting from word file to html my equations which are in the word document file was convert into image. Globals.ThisAddIn.Application.ActiveDocument.Select();...
by: TSSRALBI | last post by:
Hello I'm a network technician in training and I need your help. I am currently learning how to create and manage the different types of VPNs and I have a question about LAN-to-LAN VPNs. The last exercise I practiced was to create a LAN-to-LAN VPN between two Pfsense firewalls, by using IPSEC protocols. I succeeded, with both firewalls in the same network. But I'm wondering if it's possible to do the same thing, with 2 Pfsense firewalls...
by: adsilva | last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
by: bsmnconsultancy | last post by:
In today's digital era, a well-designed website is crucial for businesses looking to succeed. Whether you're a small business owner or a large corporation in Toronto, having a strong online presence can significantly impact your brand's success. BSMN Consultancy, a leader in Website Development in Toronto offers valuable insights into creating effective websites that not only look great but also perform exceptionally well. In this comprehensive...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.