SqlParameter 问题

Public Class SQLHelper
Public Function ExecuteDataTableSP(ByVal strSQLSP As String, ByVal params() As SqlParameter) As DataTable
        Dim oconn As SqlConnection = GetConnection()
        Dim command As New SqlCommand(strSQLSP, oconn)
        command.CommandType = CommandType.text'为何StoredProcedure不能执行？改为text就完全没问题了
        Dim dt As New DataTable
        Dim da As New SqlDataAdapter(command)
        For i As Integer = 0 To params.Length - 1
            da.SelectCommand.Parameters.Add(params(i))
        Next
        da.Fill(dt)
        da.Dispose()
        oconn.Close()
        oconn.Dispose()
        command.Dispose()
        Return dt
    End Function
End Class

sub ExecuteSql()

Dim SqlCmd As SQLHelper = New SQLHelper
        Dim paras As SqlParameter() = {New SqlParameter("@Model_Name", CStr(TextBox1.Text)),
                                       New SqlParameter("@Part_Name", CStr(TextBox2.Text)),
                                       New SqlParameter("@BuildStep", CStr(TextBox3.Text)),
                                       New SqlParameter("@Per_Use", CInt(TextBox4.Text))}

        Dim StrSql As String = "Select * from KanBanBom where Model_Name = @Model_Name and Part_Name = @Part_Name and BuildStep = @BuildStep"
        Dim myTab As DataTable = SqlCmd.ExecuteDataTableSP(StrSql, paras)
        If myTab.Rows.Count > 0 Then MsgBox("Check your data again", MsgBoxStyle.Information) : Exit Sub
end sub
'不知怎么老出错