.NET Tutorials, Forums, Interview Questions And Answers
Welcome :Guest
Sign In
Win Surprise Gifts!!!

Top 5 Contributors of the Month
Gaurav Pal
Post New Web Links

Change the connectionString in linq

Posted By:      Posted Date: December 04, 2010    Points: 0   Category :ASP.Net


i have a class library and i want to use it in difrent web form application.

i created a linq data class and i drag and drop the table of my local database in it.

now i want to use this class library in my web form application with a database in server with difrent database name but with same tables and also the connectionString Name is the same.

in my class library i call myDataContax("MyConnectionStringName")

my question is when i use a connectionstring with the same connectionString Name as my Class library ConentionString Name but with difrent database name it will work or not?



View Complete Post

More Related Resource Links

change to lambda in linq


Hello my friends I tried to change this code to lambda but I could not pleaaaase help me:


  var inforeport = from m in db.Products where m.UnitPrice > info select new { unit=m.UnitPrice,name= m.ProductName };


Change Sqldatasource or LINQ to SQL into a DataSet? [C#]

Hi Everyone,I've saw a couple of threads on here and on different sites around this area but none I've tried have seemed to work.What I'm struggling to achieve is, I want to take a set of results attained by either a SqlDataSource or a LINQ to SQL Method and feed them into a DataSet. Why? This is because I have downloaded an example of a repeater which has paging programmed on it, but in the example it uses the DataSet.ReadXML method to read a pre-defined set of results in an XML file. As my results are constantly changing I thought it would be a good idea for the DataSet to attain them from the previous mentioned ways.I've lost count at the number of ways I've tried it, from setting up SQLConnection method seperately and the QS set as a 'string' then passing that through etc. to simply trying Dataset Items = PartialClass.GetAll(); - Which throws back Generic<List> cannot be converted to DataSet - or something close to that.I'm working from an example and incorporating it into my own project.Below is the code I'm trying to get working:C#:protected void Page_Load(object sender, EventArgs e) { // Call the ItemsGet method to populate control, // passing in the sample data. ItemsGet(); } public void ItemsGet() { // Read sample item info from XML document into a DataSet DataSe

Change connection string of Linq to Sql entities

Hi all.I have a solution which uses Linq to SQL Data Classes to acced the db. I have a project for my domain objects in my solution, which is a class library and has the dbml file. When I set up the dmbl using the wizard, Visual Studio created an app.config file on that project with the connection string. It also creatting a settings file with the same info. I've noticed that if I change the connection string in the settings file, the app.config gets updated, which is the expected behaviour.However, I'm having a problem when I deploy my web site to the production server. I already set the app.config file's Build Action to "Content", and also set Copy to ouput directory to "Always". Nevertheless, when I install the web site and change the connection string in the app.config file, it still takes the old connection string, so obviously I get an error. I've found that it only works if I change it with in Visual Studio and then compile, but of course that's not an optimal solution, because any change in the production db server would mean I have to change my project's assembly, thus generating a new version.Any thing I'm missing? What do I have to configure so that the assembly takes the connection string form my app.config file directly after I deploy?Thanks a lot.

need to change the db in LINQ to SQL.



i am using LINQ to SQL in my webservice project(using vs2008).

i want to change the database.

how can i change the database while using LINQ to SQL?

can i change the database from changing the connection string in web.config file?

the new database is identical to my old database but name is changed.

please sugggest.

Multi Tenant vs Dynamically change the ConnectionString



My application is used by several customers, who needs to maintain their own database.

Currently I'm keeping all the connectionstrings and according to the user, change it. (In a case of CRUD operation).

Is this errenous way ?

I don't know much about MultiTenant applications. Is that the best solution for my problem?

SSIS Dynamic Flat Files (Can't get ConnectionString property to dynamically change)


Hi all,

I am trying to do what many have already tried.  I wish SSIS was made more user friendly in this perspective, but I am trying to have SSIS read a folder directory, and get all the files based on a condition that I've specified.

I was following this link:  http://consultingblogs.emc.com/jamiethomson/archive/2005/05/30/SSIS_3A00_-Enumerating-files-in-a-Foreach-loop.aspx

So I have a For-Each loop, and within it, I have my Data Flow Task which includes a Flat File Source Connection.  The problem is, how do I pass that information to the connection string?  I can see the connection string in the XML file, but for some reason, I cannot access the property "ConnectionString".  The first property I see when I go to the expressions editor is "DelayValidation."  Furthermore, I've seen documents online where it there is a "connectionString" property for the Flat File Source Connection.  Well, I see no such property.

Any help with specific steps would be greatly appreciated.  Also, once I've figured that part out, I need to be able to move the files to another location after they have been put in the SQL Server DB.  This was much easier in coding a vb.net application.

LINQ to DataSet in .NET 4.0 - an unwelcome change


This worked in .NET 3.5 but it does not compile in 4.0

var allergies =  from allergy in typedDataset.allergy
where allergy != string.Empty

In 4.0, I had to cast the typed dataset to IEnumerable<> using the extension method Cast<>

var allergies = from allergy in typedDataset.allergy.Rows.Cast<TypedDataSet.allergyRow>()
  where allergy.drug != string.Empty
  select allergy;

What motivated this change?  It's much less elegant now.  The compiler should take care of the messy stuff.  Will this be fixed?

Playing with Linq grouping: GroupByMany?

One of its features is grouping. Many people understand grouping like it is defined in Sql. Linq is implementing grouping quite the same way. Let's discover this syntax and how to make consecutive groups easier.

LINQ : Implementing IN and NOT IN

I got tried of typing

var result = from s in source
where items.Contains(s)
select s;and so I implemented the IN and NOT IN methods as extension methods:

101 LINQ Samples Tutorials

101 LINQ Example with sample code snippets....This sample prints each element of an input integer array whose value is less than 5. The sample uses a query expression to create a new sequence of integers and then iterates over each element in the sequence, printing its value

Linq: how to share parameters between lambda expressions ?

When using Linq to objects, you will quickly feel the need to pass some parameters from a method to another but it's not so easy because each Linq method is not calling the following one. In a Linq sequence, each method is using the result computed by the previous one. So, local contexts are not visible from one method to another.
The compiler is using two technical different ways to let parameters go out of a method.

Linq to Sql CompiledQuery container

Ok now let's go. Here is just a little trick but with some interesting patterns that could be useful in some other contexts not connected to Linq to Sql.

When using Linq expressions, like with Linq to Sql, translating the expression into something else (sql for example) is taking time and resources. Sometimes it's negligible, sometimes not...

LINQ to SQL Paging using GridView in C# and ASP.NET 3.5

This tutorial will show you how we can extend the LINQ to SQL Class and create methods that will allow us to page data from a SQL database. C# version.

What is Lambda Expressions In LINQ

A lambda expression is an anonymous function that can contain expressions and statements, and can be used to create delegates or expression tree types.

All lambda expressions use the lambda operator =>, which is read as "goes to". The left side of the lambda operator specifies the input parameters (if any) and the right side holds the expression or statement block. The lambda expression x => x * x is read "x goes to x times x." This expression can be assigned to a delegate type as follows:

How to create 3 tier application using LINQ

As you know that in 3 tier architecture there are three layers

User interface layer. (Is our Form in Windows application and .aspx page in Web application)
Data Access layer. (Which provides interface between Business logic layer and Database)
Business Logic layer.(Which stores your application logic)

Building a LINQ Provider

Throughout this article, we will build a simple IQueryable provider similar to the LINQ to SQL provider demonstrating what is needed to build a custom provider that is capable of executing LINQ queries and performing create, update and delete operations.

LINQ to SQL Performance Considerations

As developers we have a wide array of tools at our disposal. One of the most time consuming, but most beneficial tasks we must undertake is to determine which of those tools to use for a given situation.
ASP.NetWindows Application  .NET Framework  C#  VB.Net  ADO.Net  
Sql Server  SharePoint  Silverlight  Others  All   

Hall of Fame    Twitter   Terms of Service    Privacy Policy    Contact Us    Archives   Tell A Friend