---
title: clsBatchBase
summary: API reference for clsBatchBase.
status: draft
owner: <owner>
last_reviewed: 2026-07-24
library: SAIF.Presentation.ConsoleApplication
reference_type: package
---

# clsBatchBase

`clsBatchBase` (`MustInherit`, `Inherits clsConsoleBase`) is the abstract ancestor class for batch-style console applications. It extends the `clsConsoleBase` lifecycle with multi-stream, environment-variable-driven file logging and batch header/footer status reporting.

## Purpose
- Extend the `clsConsoleBase` console-application lifecycle with batch-oriented logging and status reporting for long-running or scheduled batch jobs.

## Context
- Namespace: `SAIF.Presentation.ConsoleApplication`
- Assembly/package: `SAIF.Presentation.ConsoleApplication` (NuGet package `SAIF.BOF.Presentation.ConsoleApplication`)

## Public members
| Member | Signature | Purpose |
| --- | --- | --- |
| BatchStreams | `Public Enum BatchStreams` (`StandardFile`, `File0`, `File1`, `File2`, `File3`, `File4`) | Identifies named log streams a batch application can write to. |
| WriteErrorMsg | `Public Sub WriteErrorMsg(ErrorMsg As String)` | Writes a message to `Console.Error`. |
| WriteStatusMsg | `Protected Friend Sub WriteStatusMsg(StatusMsg As String)` | Writes a message to `Console.Out`. |
| WriteAppLogMsg (console) | `Protected Friend Sub WriteAppLogMsg(AppLogMsg As String)` | Writes a message directly to the console. |
| WriteAppLogMsg (stream) | `Protected Friend Sub WriteAppLogMsg(AppLogMsg As String, LogFile As BatchStreams)` | Writes a message to a named log stream, resolving the log file path from an environment variable named after the enum value (e.g., `FILE0`), or a default `{AppName}.log` in the current directory for `StandardFile`. See [BR-001](../../business-rules.md#br-001-batch-log-stream-must-resolve-to-a-valid-file). |
| Initialize | `Protected Friend Overrides Sub Initialize()` | Overrides `clsConsoleBase.Initialize()`: calls `MyBase.Initialize()`, scans environment variables matching pattern `FILE?` to pre-register log streams in `m_AppLogs` (`Hashtable`), then calls `WriteBatchHeader()`. |
| Uninitialize | `Protected Friend Overrides Sub Uninitialize()` | Overrides `clsConsoleBase.Uninitialize()`: calls `WriteBatchFooter()`, flushes/closes any open `IO.StreamWriter` log streams, then calls `MyBase.Uninitialize()`. |
| WriteBatchHeader | `Protected Overridable Sub WriteBatchHeader()` | Writes a batch start status message (`{AppName} began at {StartTime}`) to the console. |
| WriteBatchFooter | `Protected Overridable Sub WriteBatchFooter()` | Writes batch end/elapsed-time status messages (`{AppName} ended at {EndTime}`, `{AppName} ran for {N} seconds`) to the console. |

## Inherited public members

Members in this section are inherited from `clsConsoleBase` in `SAIF.Presentation.ConsoleApplication` (this library). They are available on this type through inheritance and are not overridden by `clsBatchBase` except where noted above (`Initialize`, `Uninitialize`).

| Member | Signature | Purpose | Origin |
| --- | --- | --- | --- |
| ReturnCodes | `Public Enum ReturnCodes` | Standard set of process exit codes for console applications. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| EnvironmentService | `Protected EnvironmentService As WindowsEnvironmentService` | Concrete environment-service instance.* | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| ParameterCount | `Public ReadOnly Property ParameterCount As Integer` | Number of parsed command-line arguments. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| ReturnCode | `Public Property ReturnCode As ReturnCodes` | Maps to `Environment.ExitCode`. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| AppName | `Public Property AppName As String` | Application name used in diagnostics/log output. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| HelpText | `Public Property HelpText As String` | Text written to console by `WriteHelp()`. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| StartTime | `Public ReadOnly Property StartTime As DateTime` | Timestamp captured in the constructor. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| EndTime | `Public ReadOnly Property EndTime As DateTime` | Current time at the point of access. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| RunningTime | `Public ReadOnly Property RunningTime As TimeSpan` | Elapsed time between `StartTime` and `EndTime`. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| Execute | `Public Sub Execute()` | Template-method entry point orchestrating the console/batch lifecycle. See [BR-003](../../business-rules.md#br-003-command-line-validation-gates-application-logic). | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| GetExceptionInfo | `Public Function GetExceptionInfo(ex As Exception) As String` | Recursively formats exception details. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| GetParamName (by index/name) | `Protected Friend Function GetParamName(...) As String` (2 overloads) | Returns a parameter name by position or name. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| GetParamValue (by index/name) | `Protected Friend Function GetParamValue(...) As String` (2 overloads) | Returns a parameter value by position or name. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| ParamExists (by index/name) | `Protected Friend Function ParamExists(...) As Boolean` (2 overloads) | Returns whether a parameter exists by position or name. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| RunAppLogic | `Public MustOverride Sub RunAppLogic()` | Abstract method subclasses implement for main application logic. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| ValidateCommandLine | `Public MustOverride Function ValidateCommandLine() As Boolean` | Abstract method subclasses implement for command-line validation. See [BR-002](../../business-rules.md#br-002-case-insensitive-command-line-switch-matching). | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |
| WriteHelp | `Protected Friend Sub WriteHelp()` | Writes `HelpText` to the console. | `SAIF.Presentation.ConsoleApplication` — `clsConsoleBase` |

## Behavioral notes
- `Initialize()` and `Uninitialize()` are overrides: `clsBatchBase` layers batch-specific behavior (log-stream registration/teardown, header/footer output) around the base `clsConsoleBase` implementation, which it still calls via `MyBase`.
- Log stream file paths are resolved from process environment variables (`Environment.GetEnvironmentVariable`) named after the `BatchStreams` enum value, not from `ConfigurationManager.AppSettings`.
- All method-entry/exit tracing is delegated to `SAIF.Framework.Logging.clsLogTrace`, a framework-inherited facility not implemented locally.*

## Constraints and usage notes
- Concrete batch applications must subclass `clsBatchBase`, implement `RunAppLogic()` and `ValidateCommandLine()` (inherited abstract members), and call `Execute()` from their own `Sub Main`.
- Writing to a non-`StandardFile` log stream whose backing environment variable is unset or empty throws an exception. See [BR-001](../../business-rules.md#br-001-batch-log-stream-must-resolve-to-a-valid-file).

> **Note:** Statements marked with `*` are inferred from code behavior rather than explicit documentation or comments.

## Sources
- `Presentation\SAIF.Presentation.ConsoleApplication\clsBatchBase.vb`
- `Presentation\SAIF.Presentation.ConsoleApplication\clsConsoleBase.vb`