Thursday, December 15, 2011

WF Rule Engine

If you are trying to author Rules using the WF rule engine than 2 samples are must for reference . These are old samples but works like charm :

Samples :
External ruleset toolkit
Ruleset analyzer

Monday, November 21, 2011

MVVM Basics

Pretty Good one if you are looking for a webcast explaining MVVM pattern .

Thursday, October 27, 2011

Thursday, October 20, 2011

SOAP Request Testing Tool

I am been using the SoapUI tool for quite some time and it's pretty impressive.

You can get it from :

In order to work with Soap Request which needs authentication , there is a tab "AUT" wherein your can specify credential.

Saturday, October 15, 2011

Resource not found 404 error ( WCF Data service hosted with MVC ASP.NET)

Scenario: MVC ASP.NET application containing WCF data services. When you try to browse WCF data service .svc page you might get the error
"Resource not found -404 error" .

Reson for such behavior : When you try to browse to data service page , the request is sent to MVC framework first rather than data service . As the controller is not defined for such request , error is send back.

Resolution :Ignore request redirection to MVC framework when WCF data service is requested .In order to achieve this add following to global.asax RegisterRoute function.


Friday, September 30, 2011


{System.Data.Entity.DbUpdateException: An error occurred while saving entities that do not expose foreign key properties for their relationships. The EntityEntries property will return null because a single entity cannot be identified as the source of the exception. Handling of exceptions while saving can be made easier by exposing foreign key properties in your entity types. See the InnerException for details. ---> System.Data.UpdateException: An error occurred while updating the entries. See the inner exception for details. ---> System.ArgumentException: Parameter value '12.50000' is out of range.
at System.Data.SqlClient.TdsParser.TdsExecuteRPC(_SqlRPC[] rpcArray, Int32 timeout, Boolean inSchema, SqlNotificationRequest notificationRequest, TdsParserStateObject stateObj, Boolean isCommandProc)
at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async)
at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result)
at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(DbAsyncResult result, String methodName, Boolean sendToPipe)
at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
at System.Data.Mapping.Update.Internal.DynamicUpdateCommand.Execute(UpdateTranslator translator, EntityConnection connection, Dictionary`2 identifierValues, List`1 generatedValues)
at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter)
--- End of inner exception stack trace ---
at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter)
at System.Data.EntityClient.EntityAdapter.Update(IEntityStateManager entityCache)
at System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options)
at System.Data.Entity.Internal.InternalContext.SaveChanges()
--- End of inner exception stack trace ---

Got above error while performing of Entity Model .

The reason for failure was the decimal field in DB which was set for DECIMAL(6,5) whereas the value trying to be saved was 12.00000 .

This is how it works :

decimal of (4,1) can hold upto 999.9
decimal of (3,1) can hold upto 99.9

Tuesday, September 13, 2011

Executing Java .jar within .NET

using System.Diagnostics;

Process process = new Process();

//Path wherein Java is installed in your machine
process.StartInfo.FileName = "java.exe";
//.jar file to be executed
process.StartInfo.Arguments = @"-jar Sample.jar";

process.StartInfo.UseShellExecute = false;

process.StartInfo.RedirectStandardOutput = true;

process.StartInfo.RedirectStandardError = true;


//Get the output from stream

//in case of no error ExitCode will be zero
//In case of error , get error description
string error = process.StandardError.ReadToEnd();



Tuesday, August 16, 2011

An entity object cannot be referenced by multiple instances of IEntityChangeTracker.

I got this error due to using separate context object for an entity. I had to use same context object to perform multiple operations in Entity .

Friday, August 12, 2011

Request Error

Getting generic request error while browsing ?Set the includeExceptionDetailInFaults = true in web.config in order to get some descriptive error message.

Specified named connection is either not found in the configuration, not intended to be used with the EntityClient provider

I got this error when i was trying to browse the WCF data Services. The resolution for this issue was to define the connection string for database defined in in app.config file to the web.config file of the web application.

In Nutshell , below is my scnerio :

Project 1 : Contains the .edmx and app.config file

Project 2 : Contains the .SVC referencing entity model defined in project 1 and web.config file

Resolution :
Copy the Db connection defined in app.config to web.config under configuration section .

Thursday, July 21, 2011

Format ComboBox ExtJS

items: [
xtype: 'combobox',
fieldLabel: 'State',
store: 'TestStore',
queryMode: 'local',
displayField: 'State',

listConfig: {
getInnerTpl: function () {

return '


Tab Inside a Tab ExtJS

Ext.create('Ext.TabPanel', {
renderTo: Ext.getBody(),
id: 'main-tabs',
height: 300,
width: 600,
activeTab: 0,
defaults: {
padding: 10
items: [{
xtype: 'tabpanel',
title: 'Tab 1',
id: 'tab1',
activeTab: 0,
padding: 5,
border: true,
plain: true,
defaults: {
padding: 10

items: [{
title: 'Sub-tab 1',
id: 'subtab1',
html: 'Sub-tab 1 content'
title: 'Sub-tab 2',
id: 'subtab2',
html: 'Sub-tab 2 content'
title: 'Sub-tab 3',
id: 'subtab3',
html: 'Sub-tab 3 content'
title: 'Tab 2',
id: 'tab2',
html: 'Tab 2 content'
title: 'Tab 3',
id: 'tab3',
html: 'Tab 3 content'
title: 'Tab 4',
id: 'tab4',
html: 'Tab 4 content'
title: 'Tab 5',
id: 'tab5',
html: 'Tab 5 content'


Adding panel to ViewPort (ExtJS)

Add Panels to ViewPort on the fly

1) Define ViewPort

viewport = Ext.create('Ext.container.Viewport', {
layout: {
type: 'border'
defaults: {
split: false
items: [{

region: 'center',
layout: 'border',
frame: false,
padding: '0 5 0 0',
border: false,
items: [{
region: 'center',
items: [
xtype: 'grid1'



region: 'south',
frame: false,
padding: '0 5 0 0',
border: false

2) Add panel on the fly to defined region. In our example we are adding panel to "South" region

southRegion = viewport.getComponent(1);

southRegion .add(myPanel);

southRegion .setWidth(200);

southRegion .doLayout();

Tuesday, July 19, 2011

Remove Special character from String

string Formatted = Regex.Replace(, @"[\-]", "");

Regular Expression for YYYYMM

Well i managed to make this one for now. If you have better one please share .



PASS : 200901 , 201012 ...

FAILS :211001 , 200913 ...

Sunday, July 17, 2011

Friday, July 08, 2011

Get Security Information from Client

In order to get the security information from client in a Service , use the following Class :

ServiceSecurityContext Class


More Information:

Wednesday, June 22, 2011

Message: Expected identifier, string or number

If you get this error in your Ext JS page , then there is big possibility that you have added a extra comma which is not required .

Incorrect entry
title: 'Main Content',
collapsible: false,
region: 'center',
layout: 'fit',
margins: '5 0 0 0',
xtype: 'panelbais' , }

Correct entry

title: 'Main Content',
collapsible: false,
region: 'center',
layout: 'fit',
margins: '5 0 0 0',
xtype: 'panelbais' }

Check out the last comma before the closing curly braces .

Monday, June 20, 2011

'undefined' is null or not an object in ext-all.js

One more ext-all.js error . This time it was due to extra comma in object literal definition.

Resolution :
Find and remove extra comma.

'flex' is null or not an object in ext-all.js

I got this error for quite some time and i had no clue what was wrong in my page . Page consisted of only 2 panel controls . That's all

After playing around with some of properties of panel , the issue was resolved.

Issue in my case :
First panel had property layout: 'anchor'
Second Panel had property layout: 'border '

Resolution :
Changed the second panel property layout: 'anchor'

This might not be your case . This error is very generic and can pop up due to multiple reasons .

Ext JS : Data Model proxy for Json and XML return type


If you data is returned in JSON format then your proxy for Data Model will look like :
Ext.define("Post", {
extend: '',
type: 'rest',
url : '',
reader: {
type: 'json',
root: 'CUSTOMER'

XML Return Data

Ext.define("Post", {
extend: '',
proxy: {
type: 'ajax',
url : '',
reader: {
type: 'xml',
record: 'CUSTOMER'

Ext JS Programming Basic Requirement

So , if you have started working with Ext JS make sure you are using the following tools . Believe me they are quite handy and saves you from head banging ;-)

1) Fiddler
2) Scripting client
3) REST Service Tested ( Firefox)
4) Firebug

Thursday, June 16, 2011

Could not find default endpoint element that references contract 'x' in the ServiceModel client

Scenario :

I was creating a WCf client to test the services . After creating client proxy and testing the services i bumped into below error. It seems the configuration in my app.config was not correct.

{System.InvalidOperationException: Could not find default endpoint element that references contract 'x' in the ServiceModel client configuration section. This might be because no configuration file was found for your application, or because no endpoint element matching this contract could be found in the client element.

Resolution :
When you generate client using the svcutil.exe , an output.xml is generated. This file contains the end point configuration information . Take the configuration from this file and add it to app.config. Service should work without configuration issue assuming your code is not erroneous ;-)

Wednesday, June 15, 2011

Visual Studio IntelliSense to show comments for the Custom Function

If you added Summary to your custom defined function and it's still now showing description as part of Visual Studio IntelliSense then for sure you are missing a setting .


This is test function

public void TestFunction()
//Do something...

when you access this function , you expect the description to show up but in case its shows nothing . Then do this :

1) Open Projects property page
2) Click the Build Tab
30 Check the "Xml documentation file " checkbox

Compile project and try once more ...

Wednesday, June 08, 2011

Accessing Enterprise Application Blocks

There are mutiple ways to access application blocks :

Using the Enterprise Library Service Locator

var writer = EnterpriseLibraryContainer.Current.GetInstance();
writer.Write("I'm a log entry created by the Logging block!");

var customerDb
= EnterpriseLibraryContainer.Current.GetInstance("Customers");

The Sophisticated Approach — Accessing the Container Directly

var theContainer = new

var writer = theContainer.Resolve();
writer.Write("I'm a log entry created by the Logging block!");

var customerDb = theContainer.Resolve("Customers");

Check out this diagram :,v=PandP.50).png

Gray Failures: What is it and how to detect one?

If you are reading this article , i guess you are curious to know about gray failures and different methods to detect gray failures.  Hopefu...