How to Use a parameter within SQL in Vb 2010 (web developer) - asp.net

Question

I am trying to work out SQL code in VB but I am having problems I have a simple database with the table admin with the columns UserName and Password.
I want to be able to read data from a text box and then input it into a SQL string… the SQL string works (I've tested it) and I can get it to output with a simple SELECT statement but I can't seem to get the SQL to read my Parameter.
Help?
Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Call Password_Check(txtTestInput.Text)
End Sub
Public Sub Password_Check(ByVal Answer As String)
Dim con As New SqlConnection
Dim cmd As New SqlCommand
Dim parameter As New SqlParameter("#Username", Answer)
Try
con.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings("Database1ConnectionString1").ConnectionString
con.Open()
cmd.Connection = con
cmd.CommandText = " SELECT Password FROM Admin WHERE (UserName = #Username)"
cmd.Parameters.Add(parameter)
Dim lrd As SqlDataReader = cmd.ExecuteReader()
While lrd.Read()
Dim sothing As String
sothing = lrd("Password").ToString
If lrd("Password").ToString = txtPassword.Text Then
lblTestData.Text = "passwordSuccess"
ElseIf lrd("Password").ToString <> txtPassword.Text Then
lblTestData.Text = "passwordFail...:("
End If
End While
Catch ex As Exception
lblTestData.Text = "Error while retrieving records on table..." & ex.Message
Finally
con.Close()
End Try
End Sub

Answer 1

in your code above:
--> Dim parameter As New SqlParameter("#Username", Answer)
Can I suggest two options:
Dim parameter As New SqlParameter("#Username", sqldbtype.nvarchar)
parameter.value = Answer
or
cmd.CommandText = string.format("SELECT Password FROM Admin WHERE (UserName = {0})", Answer)
Full Code:
Public Sub Password_Check(ByVal Answer As String)
Dim con As New SqlConnection
Dim cmd As New SqlCommand
Dim parameter As New SqlParameter("#Username", SqlDbType.NVarChar)
parameter.Value = Answer
Try
con.ConnectionString = System.Configuration.ConfigurationManager.ConnectionStrings("Database1ConnectionString1").ConnectionString
con.Open()
cmd.Connection = con
cmd.CommandText = "SELECT Password FROM Admin WHERE (UserName = #Username)"
cmd.Parameters.Add(parameter)
Dim lrd As SqlDataReader = cmd.ExecuteReader()
While lrd.Read()
Dim sothing As String
sothing = lrd("Password").ToString
If lrd("Password").ToString = txtPassword.Text Then
lblTestData.Text = "passwordSuccess"
ElseIf lrd("Password").ToString <> txtPassword.Text Then
lblTestData.Text = "passwordFail...:("
End If
End While
Catch ex As Exception
lblTestData.Text = "Error while retrieving records on table..." & ex.Message
Finally
con.Close()
End Try
End Sub

Answer 2

Regarding to your Database system it is possible that it does not support parameter names. Have you tried ? Wat DB System you used?
cmd.CommandText = " SELECT Password FROM Admin WHERE (UserName = ?)"