ImageButton

Do remember to always set your ImageButton with ImageUrl. If the property of ImageUrl is blank, then it will postback twice for attend to get the value.

AutoEventWiredUp

If you think you are not using any ImageButton and your webform is triggering postback twice, most probably is due to the AutoEventWiredUp attribute. In VB.NET, whenever you add new webform, this property will auto set to False, while in C#.NET, whenever you add new webform, this property will auto set to True. Therefore, if you are developing ASP.NET application using VB.NET then you are safe. My advice for C#.NET web developer is to always set this AutoEventWiredUp to False and manually code the handler for any of Events.

Else…

If you are still facing this postback twice problem which are not due to ImageButton and AutoEventWiredUp, then probably you have to search around Google and you might found the solution.

No related posts.

MaximumASP is happy to announce the launch of a free hosting account to kick the tires of the latest and greatest from Microsoft – ASP.NET 4 and Visual Studio 2010.

This is cool I think to test out new dot net framework. I would like to test with Entity Framework 4

Posted via web from Ervin Ter’s posterous

Related posts:

1. Fresh Mind with Good Sleep Fresh Mind with Good Sleep After being so busy over...
2. AirAsia.com – Year End Extra Flights Promotion Year End Extra Flights Year End Extra Flights –> Effective...
3. C# Send New Post to Posterous Posterous has a set of API for developer to call...

Sys.InvalidOperationException: Handler was not added through the Sys.UI.DomEvent.addHandler method.

Cause:

Unknown handler error in MicrosoftAjax.debug.js

Resolution:

To ensure your server not prompting this debug message on your test or production server, just set debug=”false” in web.config. By doing this, ASP.net will not automatically include MicrosoftAjax.debug.js into one of the resource.axd

No related posts.

In this post, I am using jQuery to consume ASP.NET handler through a simple javascript codes. In the normal scenario, if client side requesting a simple string, server just have to return response context with plain/text. If you wish to return a set of data to be return in formatted string, you can either have the options like text/xml or application/json. My example code here will be using application/json with the assistance of third party component, Newtonsoft Json.

Scenario

“I Wish to use javascript to execute a job asynchronously to ASP.NET and receiving set of data in object. I do not wish to make my asynchronous call to any of my ASP.NET aspx pages because it is not a best practice. How can I do it?”

Expectation

• Data return from server in JSON object
• Calling ASP.NET handler
• Using jQuery

Prerequisite Component

• jQuery 1.3.2
• Newtonsoft Json

Solution File Structure

Download hellojson_050509_1229

Related posts:

1. Microsoft Application Architecture Guide 2nd Edition from Patterns & Practices Microsoft Patterns & Practices released the 2nd edition of their...
2. ASP.NET MVC – How to implement querystring In this tutorial, I would like to share with you...
3. Tips: ASP.NET Webform Postback Twice If your ASP.NET webform is postback twice, then you are...

The purpose of this control is to allow user to input control such as Button, Drop Down List, Radio Button List, Radio Button, List Box, Check Box List, Check Box and TextBox into each row of tree view. Additionally, I used JQuery assisting this tree view’s behavior of Collapse and Expand.

Result of this Extend Tree View as below:

Click here to see action in video:extend-tree-view

Example of the picture above showing the tree consisting 2 root with 1 level of sub-tree. Let’s see on “TICKET” root, there is a label with drop down list. This enabling user to check on “TICKET” and there is an input control allowing user to select which “TICKET” type (just an example scenario).

To begin with using the this tree, just drag and drop this tree view control from your sidebar or you can code as below:

Attached with this post the source code of this composite control with a demo web project: Download source code here

Related posts:

1. ASP.NET MVC – How to have multiple submit button in form In this tutorial, I would like to share simple form...
2. 20 Google Wave Invitations [Finished] For those of you who are really need google wave...