Access an object on one form from another?

[JamesB]

Hello,
I have a (hopefully simple) problem.

I have a form, lets call it frmMain, and this has a database connection
object on it (sqlconnection) declared as public. All works well.

One of the operations I want to do will occur on a second form (call it
frmChild).

I can open up this quite happily with

frmChild NewChildForm = new frmChild();
frmChild.showdialog();

but on the child form I want to do a Database operation. frmMain.dbconn
(name of my connection) doesn't work, and from what I have read this is
because I need an object reference to frmMain rather than just frmMain. I
get that, but how do I reference something that already exists rather than
creating a new one?
Hope that makes sense

James.

 

[JamesB]

Hello,
I have a (hopefully simple) problem.

I have a form, lets call it frmMain, and this has a database connection
object on it (sqlconnection) declared as public. All works well.

One of the operations I want to do will occur on a second form (call it
frmChild).

I can open up this quite happily with

frmChild NewChildForm = new frmChild();
frmChild.showdialog();

but on the child form I want to do a Database operation. frmMain.dbconn
(name of my connection) doesn't work, and from what I have read this is
because I need an object reference to frmMain rather than just frmMain. I
get that, but how do I reference something that already exists rather than
creating a new one?
Hope that makes sense

James.

Actually - I think I worked it out?

Added a property to frmChild:

public frmMain MyParentForm;

then in the code in frmMain that opens the child I added:

frmChild.MyParentForm = this;

I can then see MyParentForm.DBConn from frmChild...
not run it yet, but is this the correct method to use?
James.

 

[wang8254]

sure you does. It will work perfect.
acturally, you can use the following code:

in frmMain replace
frmChild NewChildForm = new frmChild();
frmChild.showdialog();
with:
frmChild NewChildForm = new frmChild();
NewChildForm.Owner = this;
frmChild.showdialog();
and in formChild when you would use frmMain,insert the following code:
frmMain fm = this.Owner as frmMain;
and now ,fm is a reference of frmMain