Storing multiple values from SQL Server statement - vb.net

Question

Consider the following code
Dim cmd As New SqlCommand("SELECT * FROM [UserDetail].[User] where UserName = #username and UserPass = #password", con)
cmd.Parameters.AddWithValue("#username", login_username.Text)
cmd.Parameters.AddWithValue("#password", hash_pass)
Dim da As New SqlDataAdapter(cmd)
Suppose that there exist a column name status I want to store the result of status in a variable.
P.S I am a beginner with VB.NET so please bear with me

Answer 1

You can execute the statement on a SqlDataReader or fill DataTable. An example with SqlDataReader is
Dim reader As SqlDataReader
Dim cmd As New SqlCommand("SELECT * FROM [UserDetail].[User] where UserName =#username and UserPass=#password", con)
cmd.Parameters.AddWithValue("#username", login_username.Text)
cmd.Parameters.AddWithValue("#password", hash_pass)
reader = cmd.ExecuteReader()
Dim strStatus as String = ""
If reader.HasRows Then
reader.Read()
strStatus = reader.Item("status").ToString
End If
Here is the DataTable version
Dim cmd As New SqlCommand("SELECT * FROM [UserDetail].[User] where UserName =#username and UserPass=#password", con)
cmd.Parameters.AddWithValue("#username", login_username.Text)
cmd.Parameters.AddWithValue("#password", hash_pass)
Dim da As SqlDataAdapter = New SqlDataAdapter()
Dim dt As DataTable = New DataTable("TableA")
da.SelectCommand = cmd
da.Fill(dt)
Dim strStatus as String = ""
'you can process the DataTable in a for/for each loop or process a single row as follows
If dt.Rows.Count > 0 Then
strStatus = dt.Rows(0).Item("status").ToString()
End If

Answer 2

If status returns a single cell value(single row in status column) then you can use following method
Dim cmd As New SqlCommand("SELECT * FROM [UserDetail].[User] where UserName = #username and UserPass = #password", con)
cmd.Parameters.AddWithValue("#username", login_username.Text)
cmd.Parameters.AddWithValue("#password", hash_pass)
Dim status As String
status = IIf(IsDBNull(cmd.ExecuteScalar), "Not Available", cmd.ExecuteScalar)
'IsDBNull is used tocheck whether cmd.ExecuteScalar is null or what
'IIF() is used to handle null here, You can assign custom value for status variable if
'select returns null value
'If you dont need to use them its possible to write
' status = cmd.ExecuteScalar
See more about ExecuteScalar()