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Introduction

A similar article was written on this subject but this article deals with accessing DataLinks from a .NET program to get or edit a connection string. Your project must reference DataLinks and ADODB, then execute the PromptNew or PromptEdit methods.

Step by step procedure

1. Reference ADODB in your project. This is required to read the COM object passed back from DataLinks. This file is located here: c:\Program Files\Microsoft.NET\Primary Interop Assemblies\adodb.dll
2. Reference DataLinks in your project. DataLinks used to be MSDASC.dll, but has changed to OLEDB32.DLL (see KB). This file is located here: C:\Program Files\Common Files\System\Ole DB\OLEDB32.DLL
3. Create a text box and a button on a Windows Form. In the button's click event, use this code:

private void ButtonGetConnectionString_Click(object sender, 
  System.EventArgs e)
{
   /* 
        Reference DataLinks
        NOTE: Reference 
              C:\Program Files\Common Files\System\Ole DB\OLEDB32.DLL
              (Was MSDASC.dll) 
        SEE:
           http://support.microsoft.com:80/support/kb/articles/Q225/1/32.asp
   */
      MSDASC.DataLinks dataLinks = new MSDASC.DataLinksClass();
      //note that a reference to: 

      //  c:\Program Files\Microsoft.NET\Primary Interop Assemblies\adodb.dll

      //is also required to read the ADODB._Connection result

      ADODB._Connection connection;                         
      //are we editing an existing connect string or getting a new one?

      if(this.txtConnectionString.Text==String.Empty)
      {     
            // get a new connection string

            try   
            {           
               //Prompt user for new connect string

               connection = (ADODB._Connection)dataLinks.PromptNew();
               //read result

               this.txtConnectionString.Text=
                    connection.ConnectionString.ToString();
            }
            catch(Exception ex)     
            {
                  MessageBox.Show(ex.ToString());     
            }
      }
      else
      {     
            // edit connection string

            connection=new ADODB.ConnectionClass();
            connection.ConnectionString=this.txtConnectionString.Text;
            //set local COM compatible data type

            object oConnection=connection;
            try   
            {     
                  //prompt user to edit the given connect string

                  if((bool)dataLinks.PromptEdit(ref oConnection))
                  {
                        this.txtConnectionString.Text=
                             connection.ConnectionString;
                  }
            }
            catch(Exception ex)
            {
                  MessageBox.Show(ex.ToString());     
            }
      }
}

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Problem with the waitcursor PrimozPayton 3:44 25 Aug '08   I have problem with the wait cursor. It appears when I call PromptEdit method on MSDASC.DataLinks object. I can't disable it. I would be very greatfull, if somebody tells me what I doing wrong or how could I fix it. Best regard, Primoz My code: ------ ///this funcion calls, when I click on Browse button into parentControl. public static bool BrowseConnectionString(Control parentControl, ref string connectionString, ref string dataSource) MSDASC.DataLinks dataLinks = new MSDASC.DataLinksClass(); ADODB.ConnectionClass connection = new ADODB.ConnectionClass(); if (parentControl != null) dataLinks.hWnd = parentControl.Handle.ToInt32(); if (string.IsNullOrEmpty(connectionString)) connection.ConnectionString = "Provider=SQLOLEDB.1;"; else connection.ConnectionString = connectionString; object objconnection = connection; if ((bool)dataLinks.PromptEdit(ref objconnection)) { ... } ----- Sign In·View Thread·PermaLink 1.00/5 SqlClient Issue with Provider Property Brady Kelly 0:07 29 Jul '07   I just found your code now after building a similar class last year. I was doing some Googling to clear up some issues and came across your article, and I thought I'd share an experience with you. When editing ADO.NET SqlClient connection strings, that don;t include a "Provider=xxx;" part, on opening a connection the dialogue selects the default ODBC provider, where one is used to seeing the SQL Server Provider. I worked around this issue by adding a flag to my class, IsSqlServerProvider, that when set, automatically adds a Provider=SQLOLEDB.1;" to 'incoming' connection strings, so that the editor selects the correct provider for editing, and then removes this from 'outgoing' strings so that the SqlClient provider doesn't complain. However, I had one problem I had to solve with a kludge: sometimes the editor added "Provider=SQLOLEDB;", without the ".1", so my stripping code missed it. I cannot find why it sometimes adds the ".1" and sometimes not, on the same server and same database, so for now I check for both in some rather smelly code. Sign In·View Thread·PermaLink No need for interop Sergey Prokhorenko 0:38 25 Jun '07   There's no need for ADO interop assembly. We can use the same method to get the connection string: string connstr = (string)str.GetType().InvokeMember("ConnectionString", BindingFlags.GetProperty, null, str, new object[0]); Sign In·View Thread·PermaLink Re: No need for interop Sergey Prokhorenko 0:42 25 Jun '07   Sorry, I didn't read the article carefully enough We can use reflection and avoid interop assemblies: Type type = Type.GetTypeFromProgID("DataLinks"); object links = Activator.CreateInstance(type); object str = type.InvokeMember("PromptNew", BindingFlags.InvokeMethod, null, links, null); object s = str.GetType().InvokeMember("ConnectionString", BindingFlags.GetProperty, null, str, new object[0]); There's user interaction anyway - reflection won't add significant slowdown here. Sign In·View Thread·PermaLink 4.00/5 Re: No need for interop Brady Kelly 23:58 28 Jul '07   What is the main benefit of avoiding interop assemblies? Sign In·View Thread·PermaLink 2.00/5 Speed akorolev10 1:24 3 Oct '04   IS AdoDB faster ADo.NEt SqlClient test Sign In·View Thread·PermaLink 1.00/5 Great! Give me exact what I am looking for zhoulhh 8:39 1 Jul '04   Thanks. Sign In·View Thread·PermaLink PromptEdit(ref connectionString) UnderEducated 11:33 10 Mar '04   What am I missing? It is my understanding that PromptEdit takes an object reference to and ADODB Connection, not an object reference to a string? The downloaded code fails with: "Connection object is not valid. No such interface supported." because of this. It would be nice if it worked, using the ADODB.Connection the end user must specify the "Allow saving password" to get the connection.ConnectionString property to return the password. If a string would work like this the user wouldn't have to check the box? Sign In·View Thread·PermaLink 2.00/5 Re: PromptEdit(ref connectionString) DanMayer 11:55 10 Mar '04   You are correct. The code has been updated. I suspect the password issue is by design, do you agree? Sign In·View Thread·PermaLink Re: PromptEdit(ref connectionString) UnderEducated 13:03 10 Mar '04   Bummer, unless the user checks the "Allow saving password" which sets Persist Security Info=True the connection string will no longer contain the password entered. Sign In·View Thread·PermaLink Re: PromptEdit(ref connectionString) [modified] mlgray 0:06 4 Jul '06   Here is a partial solution to the password issue. With PromptEdit (because it takes a reference to an ADODB.Connection instance) you can setup the Connection object that you pass to PromptEdit so that you can get the password. The Connection class has a Properties member that is a collection of key/value pairs (although the values can be, and often are, null). Many of the properties included in the collection are familiar ("Initial Catalog", "Data Source", "Password", etc.). And one of those properties is "Persist Security Info". You can get and modify this property with the folloing bit of code: ADODB.Connection connection = new ADODB.Connection(); ADODB.Property persistProperty = connection.Properties["Persist Security Info"]; persistProperty.Value = true; This causes some non-intuitive behavior: 1) The "Provider" tab will not appear in the dialog box. 2) The ConnectionString property of the Connection instance will still not include the password (unless the user checks the "Allow saving password" check box). 3) (This is the important bit.) The "Password" property will contain the password that the user enters, regardless of what the user does with the "Allow saving password" check box. 4) Coming out, the "Persist Security Info" will refelect the state of the "Allow saving password" check box. 5) Setting the "Persist Security Info" does not set the default state of the "Allow saving password" check box, but setting other properties (such as "Initial Catalog") does set default values in the dialog box. I have not been able to find a away around the "Provider" tab disappearing. Since I am only interested in SQL databases (for the moment), I just set the "Provider" property on the Connection object before calling PromptEdit as follows: connection.Provider = "SQLOLEDB.1"; For some reason any access of the "Properties" method of the Connection instance that you pass to PromptEdit prior to calling PromptEdit will cause the "Provider" tab to disappear. This is true even if you just get the count for the properties collection. In any case, the password can be retrieved with this line of code: string password = connection.Properties["Password"].Value.ToString(); Remember that the ConnectionString property may or may not include the password, so you will likely not be able to just use the connection string without some processing. -- modified at 5:06 Tuesday 4th July, 2006 Sign In·View Thread·PermaLink 2.00/5 Re: PromptEdit(ref connectionString) yetty2000 7:10 26 Oct '07   I want to be able to select a provider on the provider tab. Then go to the connection tab. In connection tab I want to check the "allow saving password" checkbox and hide it as well programmatically. Is there any way of doing it? Or in other words all i want is to be access the password from the connection tab regardless of whether the "Allow saving password" checkbox is selected or not. Any help greatly appreciated. Sign In·View Thread·PermaLink Re: Very Slow... VHsu 20:41 13 Feb '04   Why is this slow??? Sign In·View Thread·PermaLink Re: Very Slow... DanMayer 7:45 14 Feb '04   Of course, there is nothing slow about calling PromptXXXX(). However, it would be very slow to rewrite OleDb32.dll. Sign In·View Thread·PermaLink Re: Very Slow... mgarins 5:20 19 Feb '04   I am sure he probably did not even try the code ... he just saw the COM interop and immediately thought slow which is not always true.... This tip is a great way to provide an easy to develop way to create an UI for generating connection strings. I have not profiled what goes on in VS.NET when in server explorer under Data Connections what code is being run when one chooses New Data Connection.. My guess is code similar to this. Marty Sign In·View Thread·PermaLink Re: Very Slow... Ricardo Casquete 0:55 18 Feb '06   Really matters the Time ??? I am developing an Application to configure the Production Servers of our Customer and I am using the UDL to avoid the customer to edit manually the Enterprise Library Data Access Files Config Files Who mind's a seconds??? Very Good Article, you solve my problem with the PromptEdit() ps: Maybe it could be a good idea to give the Exact Name of the COM component because also this can be added in the COM tab, the component is "Microsoft OLE DB Service 1.0 Component Type Library" ( a pity this dll don't have a strong Name, I cannot sign this part of the project.... Ricardo Casquete Sign In·View Thread·PermaLink 1.67/5

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