sqlcommand question

[Agnes]

I got a silly question about Sqlcommand . In my form, there are 5 methods
which use the same sqlcommand to execute reader.
I had create and dispose for each sqlcommand in every method. Some said
that I can only delcare one sqlcommand and re-use it in every
method and no need to dispose until form closed. I am wonder which approach
is correct.
public class myform
Dim cmdSearch As New SqlClient.SqlCommand

method 1
method 2
method 3

my approach
public class myform
method1
Dim cmdSearch As New SqlClient.SqlCommand
........
cmdSearch.dispose
method2
Dim cmdSearch As New SqlClient.SqlCommand
........
cmdSearch.dispose
method3
Dim cmdSearch As New SqlClient.SqlCommand
........
cmdSearch.dispose
............