On my class module:

Public Sub OptListTwoVal(ByVal List As Object, ByVal sQuery As String, ByVal sConn As String)
    Using LibConn As New System.Data.SqlClient.SqlConnection(sConn)

      LibConn.Open()
            Dim cu As New System.Data.SqlClient.SqlCommand(sQuery, LibConn)
            Dim cr As System.Data.SqlClient.SqlDataReader = cu.ExecuteReader()
      With cr
        If .HasRows Then
          While .Read
            List.Items.Add(New ListItem(.Item(1).ToString, .Item(0).ToString))
          End While
        End If
      End With
    End Using
  End Sub

On my Page:
 

I am adding a parameter like this

            LibMain.sSelect = "EXEC spt_PhysiciansModule"
            Try
                 LibMain.AddParameter("@QType", SqlDbType.Char, "A", , ParameterDirection.Input)
                LibMain.AddParameter("@Desc1", SqlDbType.Char, "", , ParameterDirection.Input)
                LibMain.AddParameter("@Desc2", SqlDbType.Char, "", , ParameterDirection.Input)
                LibMain.OptListTwoVal(ddlPhyType, LibMain.sSelect, LibMain.connClaims)
            Catch ex As Exception

The error msg is

{"Procedure or Function 'spt_PhysiciansModule' expects parameter '@Qtype', which was not supplied."}

whats wrong with my code? please help..

You need to provide a value for the parameter:

Dim sQuery As String = "spt_PhysiciansModule"
Dim cu As New SqlCommand(sQuery, sConn)
cu.CommandType = CommandType.StoredProcedure
cu.Parameters.AddWWithValue("QType", somevalue)
cu.Parameters.AddWithValue("Desc1", someothervalue)  etc

 You can read here for parameterized queries

http://www.aspsnippets.com/post/2009/02/09/Parameterized-Queries-ADONet.aspx

 It doesnt work with the code above.

Dim sQuery1 As String = "spt_PhysiciansModule"

Dim cu As New SqlCommand(sQuery1, LibConn)

Dim cr As System.Data.SqlClient.SqlDataReader = cu.ExecuteReader()

cu.CommandType = CommandType.StoredProcedure

cu.Parameters.AddWithValue("@QType", "A")

cu.Parameters.AddWithValue("@Desc1", "")

cu.Parameters.AddWithValue("@Desc2", "")

Error Msg: Procedure or Function 'spt_PhysiciansModule' expects parameter '@Qtype', which was not supplied.

You are adding the parameter as @QType in .net where as the parameter in sql is @Qtype.

try the below line.

cu.Parameters.AddWithValue("@Qtype", "A")

 whats the difference?

mine is

cu.Parameters.AddWithValue("@QType", "A")

Command parameters in .net are case sensitive. @QType is different from @Qtype

cshark:

Command parameters in .net are case sensitive

I don't think it is .NET that is case sensitive. I think the sensitive Collation setting of the SQL Server requires the parameters to be case sensitive....

The problem is that you are creating a 'Text' command rather than a 'StoredProcedure' command. If you set cu.CommandType to CommandType.StoredProcedure and change the query to "spt_PhysiciansModule", the query will work.

Alternatively, if you can't change the command type, you need to specify the parameters in the query:

EXEC spt_PhysiciansModule @QType = @QType, @Desc1 = @Desc1, @Desc2 = @Desc2

The names need to be specified twice so that SQL matches the parameters by name; if you just specified "EXEC spt_PhysicialsModule @QType, @Desc1, @Desc2", the parameters would be matched by position, which may not be correct.

 ok got it

if modified my class

.CommandType = CommandType.StoredProcedure
.CommandTimeout = 4000
.Parameters.AddWithValue("QType", P1)
.Parameters.AddWithValue("Desc1", P2)
.Parameters.AddWithValue("Desc2", P3)

 but i wonder if how can I make my parameters flexible.  in a way for example the stored proc that will be use has 4 parameters, since my code(class) has only designed for 3 parameters only.  how can I accomplished this?

Here's an example:

public static void ExecNonQuery(string proc, string[] Params, Object[] Values)
{
    using (SqlConnection conn = new SqlConnection(connstring))
    {
        SqlCommand cmd = new SqlCommand(proc, conn);
        cmd.CommandType = CommandType.StoredProcedure;
        for (int i = 0; i < Params.Length; i++)
        {
            cmd.Parameters.AddWithValue(Params[i], Values[i]);
        }
        conn.Open();
        cmd.ExecuteNonQuery();
    }
}

This one causes an ExecuteNonQuery() command to be executed.  You just feed it a procedure name, an array of strings for the parameter names and an array of objects that provide the values to the parameters. 

Eg:

string sql = DeleteAllExpired; // name of procedure
string[] p = new string{"id"};
object[] o = new object{TextBox1.Text};
ExecNonQuery(sql, p, o);

 I've tried converting it to VB

from

{
    using (SqlConnection conn = new SqlConnection(connstring))
    {
        SqlCommand cmd = new SqlCommand(proc, conn);
        cmd.CommandType = CommandType.StoredProcedure;
        for (int i = 0; i < Params.Length; i++)
        {
            cmd.Parameters.AddWithValue(Params[i], Values[i]);
        }
        conn.Open();
        cmd.ExecuteNonQuery();
    }
}

To

Public Shared Sub ExecNonQuery(proc As String, Params As String(), Values As [Object]())
	Using conn As New SqlConnection(connstring)
		Dim cmd As New SqlCommand(proc, conn)
		cmd.CommandType = CommandType.StoredProcedure
		Dim i As Integer = 0
		While i < Params.Length
			cmd.Parameters.AddWithValue(Params(i), Values(i))
			System.Math.Max(System.Threading.Interlocked.Increment(i),i - 1)
		End While
		conn.Open()
		cmd.ExecuteNonQuery()
	End Using
End Sub

-------------------------------------

From

string sql = DeleteAllExpired; // name of procedure
string[] p = new string{"id"};
object[] o = new object{TextBox1.Text};
ExecNonQuery(sql, p, o);

To

Dim sql As String = DeleteAllExpired
' name of procedure
Dim p As String() = New String()
Dim o As Object() = New Object()
ExecNonQuery(sql, p, o)

Are these correct?

 The problem is, the parameter in the stored procedure should be the same with the parameter declared in .net