Connecting Database using c# in Visual Studio 2013

Question

I have a problem connecting my database (created in SQL Server 2008 R2 Express) with c# in vs 2013

Here is the code I wrote

string connStr = ConfigurationManager.ConnectionStrings["newSchool"].ToString();
SqlConnection conn = new SqlConnection(connStr);

the error is NullReferenceException

What is the problem. Do you get an error message? Where is the conn.Open statement? — Patrick Hofman, Jan 06 '14 at 14:45
And why is everybody using `ConfigurationManager` when you can easily access settings using `Properties.Settings.Default`? (Yes, I'd really like to know). — Thorsten Dittmar, Jan 06 '14 at 14:46
I'd suggest including the ConnectionStrings section of your config file — Liath, Jan 06 '14 at 14:51

score 1 · Answer 1 · answered Jan 06 '14 at 15:09

1

Change this:

string connStr = ConfigurationManager.ConnectionStrings["newSchool"].ToString();

to...

string connStr = ConfigurationManager.ConnectionStrings["newSchool"].ConnectionString;

Cheers -

answered Jan 06 '14 at 15:09

simon at rcl

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score 0 · Answer 2 · answered Jan 06 '14 at 14:48

0

I assume that there is no connection string named newSchool. It is probably NewSchool or some other casing.

In response to your comment: You need to provide a proper connection string. The ConfigurationManager is used to get a value from the configuration. The NullReferenceException shows you that the setting you request is not there.

You need to create a connection string first using the settings manager and then you can access it.

answered Jan 06 '14 at 14:48

Thorsten Dittmar

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newSchool is the name of the database – user3100088 Jan 06 '14 at 14:49
2

Well, then you didn't grasp the concept of connection strings. Use the settings manager to create an actual connection string. – Thorsten Dittmar Jan 06 '14 at 14:50

score 0 · Accepted Answer · answered Jan 06 '14 at 14:48

Where did you define your connection string? In the app.config? Please send us the place where you configure this.

See http://msdn.microsoft.com/en-us/library/ms254494(v=vs.110).aspx for help.

See http://www.connectionstrings.com/ how to configure a connection string for .net

Connecting Database using c# in Visual Studio 2013

3 Answers3