How to run application with SQl database in its Form_Load in startup

Question

I have developed an application using C# on Visual Studio 2010 and SQL Server 2008. My application is like a notification program that appears when the windows starts in the Application's start-up Form_Load event it connects to the SQL database as follows

da = new SqlDataAdapter("select info_id,info_text,cat_id from info " + cat, a.GetConnectionStringByName());
SqlCommandBuilder br = new SqlCommandBuilder(da);
ds = new DataSet();
da.Fill(ds, "em");
richTextBox1.Text = "";
txt = "";
DataRow dr = GetRow();
if (dr != null)
{
    richTextBox1.Text = dr["info_text"].ToString();
    txt = richTextBox1.Text;
}

and this is my connection string

<add name="Info_Bank_Project.Properties.Settings.KBankConnectionString" connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\KBank.mdf;Integrated Security=True;User Instance=True" providerName="System.Data.SqlClient" />

When the application run in the startup when the system start, it makes an exception that says that connection timed out Does anyone have an idea about the reason of that exception and how to solve it?

What does the connection string look like? – RThomas Aug 24 '12 at 23:41 — RThomas, Aug 24 '12 at 23:41
The connection string is probably incorrect .. – Aug 24 '12 at 23:41 — , Aug 24 '12 at 23:41

Icarus · Accepted Answer · 2012-08-25T00:20:17.273

2

Connection timeout occurs while you attempt to establish a connection to the database and the Database does not respond within 15 seconds (default value).

If you get this sort of problem is because your database server is probably not listening for connections or your connection string is wrong.

edited Aug 25 '12 at 00:20

answered Aug 24 '12 at 23:41

Icarus

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thanks, What would i do to solve such a problem? i have attached the connection string. and when i debug the application i runs perfectly without any bugs – Hassanation Aug 25 '12 at 00:12

score 2 · Answer 2 · edited May 23 '17 at 10:24

2

I haven't seen a SQL connection string with a .\SQLEXPRESS as the source. I'm guessing it points to localhost? If you are running this at windows start up are you sure that SQL is up and listening on its port before this app fires off? As Icarus mentions SQL will timeout on you if it takes too long (default 15s) you can change it with the Connection Timeout field in the connection string (connection string MSDN . A better way in my opinion would be to add some logic before your connection attempt that checks to see if something is listening on the SQL port before continuing on.

The top answer for In C#, how to check if a TCP port is available? shows how to do this in C# it should fairly simple to translate into VB. You'd just put this in a loop that sleeps say for 3s and tries again until the port is being used (so the inverse of this example) for up to 20 times (1 minute) or however long you want before giving up.

edited May 23 '17 at 10:24

Community

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answered Aug 25 '12 at 00:34

Mike

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my guess is that the sql server service is not starting up on the startup. – Jason Dam Aug 25 '12 at 04:30
Jason: you could be right. Also at least for Win 7 (not sure if it is the same for the latest server addition but since it is a dev machine I'm assuming it is non-server OS) the OS gives priority at startup to base services and runs the rest at reduced priority until they are up. If this app fires up quickly but SQL (as we know it does) takes a bit to get up and going he could quite easily hit the 15s default cutoff. Heck my Win 7, 4GB i7 quad takes a good 40s from windows logo to usable with the only major thing on the box at startup being SQL. Its a beast. – Mike Aug 27 '12 at 03:41

How to run application with SQl database in its Form_Load in startup

2 Answers2