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Can't pass connection from one form to another

Posted on 2008-06-12
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Last Modified: 2013-11-26
Hi everyone,

I'm completely stuck at passing the connection info from my login form to my main form. The program should:

- Connect to the remote MySQL DB
- Fetch a list of usernames so the user select his/her
- Validate the user's password with the MD5 password stored in the DB
- If the user and password matches, show the main form
- Open the main form having the connection stablished (this is the problem)

I attached two TXT files with both forms to see if anyone can help me with this.

Thanks a lot in advanced!!
login.txt
main.txt
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Question by:Caracena
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Rurne earned 500 total points
ID: 21771756
It looks like your MySQLConnection is simply falling out of scope.   In login.txt, you define

"Public Class frmLogin
    Dim conn As MySqlConnection
    Dim myCommand As New MySqlCommand
    Dim myAdapter As New MySqlDataAdapter"


conn, myCommand, and myAdapter are thus all local properties of the frmLogin class.  As you never pass it to frmMain before calling frmMain.Show(), calling conn.Open() and conn.Close() in frmMain_Load should result in error: frmMain.conn has no parameters, as it's a completely separate MySQLConnection from frmLogin.conn.

The easiest way around this would be to define conn, not as a property of either class, but as a global MySQLConnection, which you can then reference in the appropriate namespaces.
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