connection string problem in winforms

Question

hi can any one help me how to change connections string at run time current is working with first connection string. run time i need to change second connetion when first connection not found

Bryian Tan · Answer

hi I'm not sure how your application using the setting and I assumed that you only have two connection in the app.config. If that the case you can try something like if (System.Configuration.ConfigurationManager.AppSettings[ConnectionString1] != null) { //use ConnectionString1 } else { //use ConnectionString2 }

Rohit Sharma · Answer

Step 1: Add a text File in your Project named 'ServerName' (ie.txt) Step 2: Add a class named DynamicConString and add the following code Public Class DynamicConString Private dUserName As String = sa Private dPassword As String = lock Private dServer As String 'public SqlConnection Cn() Public Function getConnString() As String Dim objReader As System.IO.StreamReader = Nothing objReader = New System.IO.StreamReader(Application.StartupPath & \ServerName.txt) dServer = objReader.ReadToEnd() objReader.Close() 'return new System.Data.SqlClient.SqlConnection(Data Source= + dServer + ;User ID= + dUserName + ;Password= + dPassword); dServer = Server= & dServer & ;Database=VoucherDB;Integrated Security=false;User Id= & dUserName & ;Password= & dPassword Return dServer End Function End Class Step 3: Call the class DynamicConnection String Add the Code in the form which starts first during project load like splash screen or Login Dim server As String = getConString.getConnString Dim config As System.Configuration.Configuration = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None) config.AppSettings.Settings.Remove(connection) config.AppSettings.Settings.Add(connection server) config.Save(ConfigurationSaveMode.Modified) ConfigurationManager.RefreshSection(appSettings)

venkata kumar · Answer

hi thanks for reply but this is finding connections from app.config first connection not found need to open with second connection

Dorababu Meka · Answer

foreach(ConnectionStringSettings con in ConfigurationManager.ConnectionStrings) { string name = con.Name; string connString = con.ConnectionString; string provider = con.ProviderName; } Select the required as per your code